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Discussion Starter #1
I'm working on a 68 coupe that has some accident damage. I'm trying to establish how the body level front to back should be in reference to the frame rail baseline before I start building a jig to put everything back in its correct location. If I level based on the assumption that the rocker panels should be parallel to the baseline, the frame measurements are waaay off. If I level according to the frame dimensions (I can only get them to within +/- 1/4"), the rocker panel is 1/2" higher in the front than the rear (measured from the front to rear of the door). Anyone happen to notice the same? I'm leaning towards leveling with the frame as close as I can get it, but was hoping someone more knowledgeable than I could tell me if that's the right way to go. It seems odd to me that the rockers wouldn't be parallel, but I honestly don't know. I suppose that suspension loading differences would bring the overall body back to level, but was hoping someone out there might be able to shed some light on my conundrum.
 

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Discussion Starter #2
I forgot to post another picture that made me question the whole thing in the first place. When I lay my export brace in place, there is a significant gap at the front of the shock towers, close to 1/2". If the front rails rotated up in the front to close the gap, it would bring the rocker panels closer to level, hence the question.
 

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I am also interested in hearing what others have to say about this. I am a long way from getting to this point, but have been contemplating how to make my jig as I continue stripping the car down. The whole underside of my car is coming off, but the rockers actually seem in pretty good shape and all of the gaps seem pretty good right now.


Hopefully I will continue to gain more understanding and enlightenment as I disassemble everything. But from my initial research, it looks like the rockers should run parallel to the datum line and the front frame rail to radiator support is slightly inclined from firewall to radiator.


I plan to use the "whole floor assembly", core support, strut braces, etc... I am going to order everything and have it on hand BEFORE I start taking anything out. I am just starting to develop a plan for some type of jig to keep the body in position and sliding the floor assembly underneath. Or more correctly, I will probably use my lift to position the body on top of the floor assembly. Lots of thoughts in my head, but no real plan yet.


Looking forward to hear how this pans out.
 

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I would take it to a body shop with a frame table/platform and get them to check and straighten it and tack in some bracing.
 

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If you have not supported the chassis correctly, you will never get good dimensions. 4 jack stands do not provide enough support for the front or rear of the chassis. Depending on what area of the car you are repairing, it should be supported in numerous places, not just at the torque box areas.


When you use the body measurement charts the datum line that they are referencing is not level to the rockers. Me personally, I built my chassis fixture to locate major assemblies; front frame rail, front of torque boxes, front leaf spring mounts and rear cross member, everything square and level. I set the chassis level at the rockers and use a laser level for the datum line underneath the car. It is much easier to have the rockers level than set at the datum line, as you are discovering. These cars are not accurate and have been subjected to who knows what all in their lifespan. Using plum bobs and tape on the floor to check the cross reference dimensions (a tram would be easier) and a metal ruler along with the laser level will get you fairly accurate dimensions without a second hand. You will find that these dimensions are all over the place and if you are replacing major structural items like the front frame rails, measure and reference all known dimensions and record them so when you go back together with new parts you can correct issues that might have come from the factory, much less collisions and other damage. Also note that some of the dimensions on the body measurement charts are not correct. Take the time to fit body parts, measure for square, use sheet metal screws before welding anything and double check all work before welding it up.
 

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I have the front chopped off my 66 right now due to old accident damage. So measurements of the front with the old sheet metal are useless... I am just now getting the front floor supports into place.

The best place to support the car is by the pinch welds and get those all in place. The problem with that is if you are using jack stands the car won't really be high enough to work on. Which is my problem right now... Ideally you could support it by the pinch welds and then be able to tie it down to the floor so it doesn't move...

As for measurements. You will not be able to rely on one drawing. There is no one drawing with all the dimensions and you need to cross check with others as there are different measurements due to some being wrong or measuring from a hole that does not exist. I have had to get the dimensions from a later model for the front floor support across to the rear frame rail because the late 66 only has the rear indexing hole... Like mentioned cars back then were not very accurate. They build cars like houses using tape measures that didn't have markings smaller than 1/4"

Here is another drawing I found that has some info that others don't have.


Your export brace gap could be just the brace itself not having the right angles. Also that nose will tend to dip when you support the car by the front of the rocker panels. because that whole nose is designed to be in compression against the firewall not in tension.


On mine once all my front end parts come in I will work at getting them all fitting where they should be and get it welded together. Then I will throw together a stand that supports the car by the front leaf spring bolts and the LCA bolts so I can get the car high enough off the ground to easily work on the quarters etc. I will also look at making it roll on it's side so I can strip and paint the bottom.


Oh and I made up some simple quick trams for playing with alignment of parts using some scrap oak and maple sticks. I found sockets the same size as the alignment holes and attached them at the proper distance. They work great for initial verification of placement. I am going to pick up some 1" aluminum tubing from a friend and make a couple permanent rods that can't move.

Shoot me a PM if you have any ideas you want to bounce off of me. This is my first mustang but i have done other cars in the past usually with the luxury of a real frame though. My build thread is here https://forums.vintage-mustang.com/build-forum/1149848-66-basket-case-4.html
 

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Discussion Starter #8
So, I've been off the forum for a while, I never seem to have enough time to work on the car continuously, only in fits and starts. I based level (datum) line on the rear frame reference points, and the steering gear/idler arm points on the front frame rails. In its past, someone had cut the front end off in front of the shock towers and brazed on a '67 front end, so the measurement to the bumper bracket holes was pretty much worthless; it wasn't even parallel with the old frame rails. This is where I'm at now, and was wondering what would be the recommended order for reassembly. Should I get the floors back in, floor supports, and then build forward from there? Firewall, cowl, then floor?

On a side note, the holes where the shock tower braces mount on the new firewall are 3/16" off center, something to watch out for! The holes in the lower cowl are off by 1/16", and the holes in the upper cowl are spot on. And here I thought it's be easy to get them all lined up:rolleyes: The left side fender apron mates up pretty well to the firewall/toe board, but the right side has quite a large gap near the top (about 1/2"). The firewall and complete frame rail assemblies are all Dynacorn parts; I kind of expected that they would fit together better than they do, especially all being from the same company. Has anyone else run into fitment issues like this? I'm thinking the best fix is to just cut and add some metal to the back of the fender apron and re-flange it to match the firewall.

I don't want to get something put in and the realize later that I should have done "X" before "Y". Right now, I'm going to wire wheel/sand as much rust as I can off the back side of the dash and get it primed and painted while it's easy to access. I have attached some pictures that might explain better that I can in words.
Misaligned Front Frame Rail.jpg LH Front Frame Rail Level.jpg Left Fender Apron to Firewall.jpg Right Fender Apron to Firewall.jpg As It Sits Now.jpg
 

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I am in the process of similar on my 69. I built a "table" from 2x2 tubing that I have leveled. The body of the car is centered on the table. The rear of the body is attached to the table with uprights that bolt to the front leaf spring mounts and the front is supported under the frame rails. As latoracing mentioned the datum line where all vertical measurements are ref from is extreamly important. On a 69 the center of the front leaf spring bolt is 6.5" above the datum line and the tq boxes are 6" above the datum line. The front of the frame rails are 12.75" above the datum line.

The horizontal surface of my table is essentialy my datum line. All measurements are from the surface to the body. In order to give myself some working room I added 3.5" to each of these vertical measurements, raising the body further fome the table.

Measuring is easy. As all I need to do is level the table and take vertical measurements and add 3.5". If I had a laser line I would just level the table and set the laser line 3.5 above the table measuring down from the body to the laser line.

I will try to post pictures if any one is interested.
 

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Discussion Starter #10
I understand what latoracing was talking about when supporting the car, but my original question was whether the rockers are parallel to the baseline. Since the front end had been moved and hacked on so much previously, I didn't know if I could trust any of those measurements. The rear frame rails seemed to be in pretty good shape as far as where they're supposed to be, as far as I can tell, so I based my datum line on the rear rails (holes in the front frame rails that were part of the original structure were fairly close). Assuming that the rear was good (even though assumption is the mother of all evils and "assume" makes an ass out of u and me), it turns out that the rockers are 5/16" higher in the front than the back; it just seemed odd to me that they would be that way. At that height, the front edges of the cowl side panels were also perfectly plumb. It may not be exact, but I had to find a happy medium. I can see where it might have been that way, since adding the weight of an engine and transmission would bring it close to level. I know of a guy who has an original '67 with somewhere around 40,000 original miles, but I don't think he'd let me strip it down to get some measurements🤣🤣🤣

I pretty much went the same route as you for a "table", only I made some 3/16" x 3" x 3" uprights that I bolted to my garage floor that mounted to the front leaf spring bolt holes and the door hinge mounting holes in the A-pillar. I question how much the car moves, though. Before I bolted them to the floor, I could easily pick up the car from either front or rear with no perceivable movement before it actually came off two of its "legs".
20190413_235500209_iOS.jpg


I built mine about 24" above the datum line referenced in the shop manual. I don't have or care to make a rotisserie, so I figured that would give me enough room to work on the bottom side. I came to the conclusion that I need to re-hang the doors to make sure everything lines up before I weld anything in, so I had to remove the front supports, hence my "body cart" I made out of what I had on hand supporting the rockers. What I don't like now is that the front end can move around. When all four supports were bolted to the floor, it was rock solid. When I'm sure that the front end sheetmetal will line up, and get the firewall and cowl panels back in, I'll put it back on the centerline I have marked on my garage floor and put the front supports back on.
 

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Here in north TX the soil has allot of clay thus temp and ground moisture play a huge role in foundation movement, especially on a concrete slab and no piers. I say if the house has not moved it is going to move. When I built mine I used a bolt and nut at the bottom of each leg so they are independently adjustable. In my case during this part of the project I moved across town so this came in really handy.

I grew up in Iowa but never had a reason be concerned with movement but not recall any issues in my area. Maybe due to a more consistant climate than north Texas.

In any case be sure to measure, measure, and measure again. I'm at the point where I should be welding it all together but am dragging my feet....
 

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Here in north TX the soil has allot of clay thus temp and ground moisture play a huge role in foundation movement, especially on a concrete slab and no piers. I say if the house has not moved it is going to move. When I built mine I used a bolt and nut at the bottom of each leg so they are independently adjustable. In my case during this part of the project I moved across town so this came in really handy.

I grew up in Iowa but never had a reason be concerned with movement but not recall any issues in my area. Maybe due to a more consistant climate than north Texas.

In any case be sure to measure, measure, and measure again. I'm at the point where I should be welding it all together but am dragging my feet....

Im NW of Fort Worth and here is the total exception to the area. We are 100% sand. I can dig holes with a flat nose shovel. But on the east side of the lake it's solid rock with solid clay mixed in... But yeah here foundation problems are the norm. It's just a matter of when and how bad it will be though new houses are built with post tension slabs which virtually eliminate the slab breaking and sinking.

Luckily where my 66 is in my shop it is nearly dead flat. Needed no shimming once I got the car off the ground.


I wish Ford would have used the rockers as the datum baseline but there is the issue of the front of the rockers curve upward from around the rear of the A pillar forward. I have mine level and it somewhat works because the new vert inner rockers don't have that upward curve and the front floor supports are level with the bottom of the rocker as well. Checked against other cars as well.

One issue I have had with it sitting on it's own weight is that the car when stripped is light I mean really light. I can easily pick up the front or rear of the car with no help. If I were to do another I would do like above and bolt it to the floor. I had started to build a steel support frame but decided it wasn't worth the work.
 

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So, I've been off the forum for a while, I never seem to have enough time to work on the car continuously, only in fits and starts. I based level (datum) line on the rear frame reference points, and the steering gear/idler arm points on the front frame rails. In its past, someone had cut the front end off in front of the shock towers and brazed on a '67 front end, so the measurement to the bumper bracket holes was pretty much worthless; it wasn't even parallel with the old frame rails. This is where I'm at now, and was wondering what would be the recommended order for reassembly. Should I get the floors back in, floor supports, and then build forward from there? Firewall, cowl, then floor?

On a side note, the holes where the shock tower braces mount on the new firewall are 3/16" off center, something to watch out for! The holes in the lower cowl are off by 1/16", and the holes in the upper cowl are spot on. And here I thought it's be easy to get them all lined up:rolleyes: The left side fender apron mates up pretty well to the firewall/toe board, but the right side has quite a large gap near the top (about 1/2"). The firewall and complete frame rail assemblies are all Dynacorn parts; I kind of expected that they would fit together better than they do, especially all being from the same company. Has anyone else run into fitment issues like this? I'm thinking the best fix is to just cut and add some metal to the back of the fender apron and re-flange it to match the firewall.

I don't want to get something put in and the realize later that I should have done "X" before "Y". Right now, I'm going to wire wheel/sand as much rust as I can off the back side of the dash and get it primed and painted while it's easy to access. I have attached some pictures that might explain better that I can in words.
View attachment 743151 View attachment 743152 View attachment 743153 View attachment 743154 View attachment 743155
I had the same exact problem getting the frame rails/inner fender area to fit up against the firewall nice as well. What I found out is it doesn't sit tight in every spot from the factory to begin with, but it should be closer then that. So I used some sheet metal vise grips an pulled out on the rear of the inner fender areas, used a block of wood an hammer and gently massaged the fire wall out some, squared the front end, pulled, twisted, tweaked, etc., to get my heights an dimensions where they needed to be. Then sheet metal screwed the hell out of it, an kept checking, pulling, etc. I bet I had a good day into it before I started welding.
 

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743356


This is how mine ended up. I still have some grinding to do in spots but I wanted to get sealer on it while I worked on different parts of the car. I'm still going to add some reinforcement around the hood mount area as those spots seem to flex a lot an I'm going to add some tack welds around the hood mount nuts too so once I'm done with all that I'll finish grinding all the welds on everything in those areas.
 

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On a side note, the holes where the shock tower braces mount on the new firewall are 3/16" off center, something to watch out for! The holes in the lower cowl are off by 1/16", and the holes in the upper cowl are spot on. And here I thought it's be easy to get them all lined up:rolleyes: The left side fender apron mates up pretty well to the firewall/toe board, but the right side has quite a large gap near the top (about 1/2"). The firewall and complete frame rail assemblies are all Dynacorn parts; I kind of expected that they would fit together better than they do, especially all being from the same company. Has anyone else run into fitment issues like this?
The four brace holes lined up pretty spot on for mine. I have a new firewall and one-piece lower cowl, both from NPD and the original upper cowl. I spent a lot of time assembling all the sheet metal, including the fenders, to align everything. The height of the rear inner-fender aprons is set by the fender. If you look at my build thread, you'll see details on that - it worked quite well and gave me comfort that they were being welded in at the right spot. The interfaces from the aprons to the firewall matched up really nice too.

I also spent time making sure the one-piece export brace was aligning everything. I used 1/2 bolts through all four holes at the firewall to make sure they were lined up. If the top of your shock towers are at the right spot, the export brace should also center up your cowl and firewall. Also, pay attention to the 40" measurement between the hood hinge flanges.

You can see in this photo how tight the curve of the passenger side inner fender well matches the curve of the firewall.
20191226_174044 by 7T02S, on Flickr

Check out my posts #69, 71, 72, 73, 77, 78 and 80 of my build thread. I went through the same process and tried to document the way I aligned everything up. You can also see the order of operations that I chose to install everything in. One thing I probably wouldn't do if I did it all over was pre-weld the frame rail extensions onto the frame rails. In hind sight, it is probably what made me realize the passenger side rail was bowed in two directions, so there are pros and cons to the order of operations. Regardless, I'm happy with how it all turned out. One important note is that the I welded the firewall in after the frame rails and torque boxes were welded in because that order made the most sense to me with all the parts out. Let me know if you have any questions!
 

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Discussion Starter #18
View attachment 743356

This is how mine ended up. I still have some grinding to do in spots but I wanted to get sealer on it while I worked on different parts of the car. I'm still going to add some reinforcement around the hood mount area as those spots seem to flex a lot an I'm going to add some tack welds around the hood mount nuts too so once I'm done with all that I'll finish grinding all the welds on everything in those areas.
Yeah, that's pretty much what mine looks like with the new parts. Factory parts are within 1/16" in that area. I think I'll straighten out the flange there, get it to fit a little better to the firewall, and then put another flange on if I think it needs it. It's not welded to the firewall there, so it may not be necessary.
 

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Discussion Starter #19
The four brace holes lined up pretty spot on for mine. I have a new firewall and one-piece lower cowl, both from NPD and the original upper cowl. I spent a lot of time assembling all the sheet metal, including the fenders, to align everything. The height of the rear inner-fender aprons is set by the fender. If you look at my build thread, you'll see details on that - it worked quite well and gave me comfort that they were being welded in at the right spot. The interfaces from the aprons to the firewall matched up really nice too.

I also spent time making sure the one-piece export brace was aligning everything. I used 1/2 bolts through all four holes at the firewall to make sure they were lined up. If the top of your shock towers are at the right spot, the export brace should also center up your cowl and firewall. Also, pay attention to the 40" measurement between the hood hinge flanges.

You can see in this photo how tight the curve of the passenger side inner fender well matches the curve of the firewall.
20191226_174044 by 7T02S, on Flickr

Check out my posts #69, 71, 72, 73, 77, 78 and 80 of my build thread. I went through the same process and tried to document the way I aligned everything up. You can also see the order of operations that I chose to install everything in. One thing I probably wouldn't do if I did it all over was pre-weld the frame rail extensions onto the frame rails. In hind sight, it is probably what made me realize the passenger side rail was bowed in two directions, so there are pros and cons to the order of operations. Regardless, I'm happy with how it all turned out. One important note is that the I welded the firewall in after the frame rails and torque boxes were welded in because that order made the most sense to me with all the parts out. Let me know if you have any questions!
I will definitely check out your build thread. I do have some all thread between my shock towers and a 2x4 screwed between the hinge mounting holes of my "clamp rack";) I do plan to hang the doors and set the cowl, fenders, and hood back in place before I start to weld anything in.
20200202_184140376_iOS.jpg
 
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