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1968 Couple to Fastback Conversion journey

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Hey everyone.

About myself. I like cars, I work in IT, and rebuilt/tune broken toys is my hobby and a little mind outlet.

I always liked 1968 Fastback design but
a) too expensive for a good one
b) bad ones were expensive and bunch of serious problems
c) i never was too big fan of the coupe (sorry to all the owners, I just liked Fastback more)

It wouldn't be possible to start this project if I would want to keep things original but I always was buying cars for fun, not to keep them in a museum.

A few years ago I started to see around videos coupe to fastback conversions and I decided to try one day myself.

I said, I better to buy car cheap, then invest money into new parts instead of giving away difference in ~25k to some person just to have it. So Coupe to Fastback idea settled down.

Last June, I was looking for a car that I would use as a donor for a conversion. I said, let it be rusted in the right places that I will cut out anyways. I should have a clean proper title. and..
I found one. It was a bit expensive, some rust around but it already had front brake conversion, was running, plus the interior wasn't too bad. Alright I said and bought this.

Car Wheel Tire Vehicle Land vehicle


the doors, fenders, rear fenders had a lot of rust, the rest was okay. IDropped on my 19" wheels. Took off 350GT rims and put them away to sell in the future.
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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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Looks like an interesting project for sure. Couple of questions popped into my head though. If you are going to cut off and discard a large amount of the rear of the car why sand and primer all that stuff?
Also you said "A lot of rust around the panels .." How was that rust damage addressed exactly?
I see you didn't bother to remove the emblems on the side of the car before primering. Guessing because you are just going to throw that stuff away. OK, but it's a lot easier to sand without it on there. Could just be me there.
 

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1966 Mustang HT, 302, GT40P, C9OX intake, rattler cam, hipo manifolds, 4r70w
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Hi Pete,

While waiting for the rest of the parts to arrive will you start with the body works on parts that will not need to be replaced? I see there is a big hole in the drivers side fender in the area that normally is covered by the rocker panel moulding.
Should be a good starting point for the body works.

Kind regards
Björn
 

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What you were planning to do is a huge task. Emphasis on the word huge. The other problem is you either end up ruining a coupe or having a fake fastback. My 65 Fastback also had a ton of rust, was in the body shop for almost 2 years. Then we had to put it all back together again (thank you Chuck Wiltens). I can’t even imagine changing a coupe into a Fastback. I don’t want to be Debbie downer but you might want to reconsider what you’re planning on doing.
 

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Discussion Starter · #25 ·
Looks like an interesting project for sure. Couple of questions popped into my head though. If you are going to cut off and discard a large amount of the rear of the car why sand and primer all that stuff?
Also you said "A lot of rust around the panels .." How was that rust damage addressed exactly?
I see you didn't bother to remove the emblems on the side of the car before primering. Guessing because you are just going to throw that stuff away. OK, but it's a lot easier to sand without it on there. Could just be me there.

Yes, I will cut it off. Just didn't want to the car look crazy for these days/weeks while I'm waiting for the parts, I still work on the suspension, taking car for a ride to test it out so, I decided to seal the whole car. Took me extra 15 minutes to do it, no biggie.

Right now I grinded and cut off the parts that were "done" except the door, I got new skin for it so it will be a weekend project for me to replace it. A pillars are also done, I just did what I could for now, but when the last parts will be here, I replace all structural elements anyway.

You right. I need to take care of the fender anyways, weld in a couple metal sheet pieces and all labels will be removed, because no need to underline that this is Mustang, everyone knows it anyway but since there so much work anyway I didn't care too much.
 

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Discussion Starter · #26 ·
Hi Pete,

While waiting for the rest of the parts to arrive will you start with the body works on parts that will not need to be replaced? I see there is a big hole in the drivers side fender in the area that normally is covered by the rocker panel moulding.
Should be a good starting point for the body works.

Kind regards
Björn
You right. I did cut a big rust hole there a couple weeks ago, sealed the edges and picking up metal sheets on Saturday morning so it will be new fun video hopefully.
 

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Discussion Starter · #27 ·
What you were planning to do is a huge task. Emphasis on the word huge. The other problem is you either end up ruining a coupe or having a fake fastback. My 65 Fastback also had a ton of rust, was in the body shop for almost 2 years. Then we had to put it all back together again (thank you Chuck Wiltens). I can’t even imagine changing a coupe into a Fastback. I don’t want to be Debbie downer but you might want to reconsider what you’re planning on doing.

After rebuilding a few cars for my tiny cars collection (including my daily bimmer where is everything is pretty much custom made), Mustang conversion sounds like slightly bigger project where I should be careful before to weld anything together.
Car Wheel Vehicle Tire Automotive tire


I do all of these projects for fun, don't limit myself budget/timewise, I like to do everything myself, this way it's hard to fail pretty much.

About true or fake, I said to myself: the difference between coupe vs fastback $25k.
in both cases you i'll get pile of .. unless you spend $150k. So, it's better to get okay coupe for dust with some rust (in the right places) then cut off bad parts, get brand new body and invest further 25k-60k into custom build suspension, engine, transmission, custom large brake/rotors system (same I did in the bimmer) no tiny wilwood, rims and etc. and drive something that you like as a design, punch it to 3.5-4s to 60 and.. I never never sell cars.
 

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While I don't care about the whole "real" or "fake" fastback thing(I am far from a concours guy as you could get), from my point of view, its a shame to see another coupe sacrificed at the altar of the fastback. That being said...if you are an experienced welder(or even if you are not, as long as you have the drive) its not that difficult of a conversion for 67-68(more difficult for 65-66). I think I would still opt for a fiberglass body on a roadster shop chassis though and spend the time on fit and finish instead when you are talking about a budget of 25k+, since originality isn't a concern....you could get more for less.
 

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Discussion Starter · #33 ·
While I don't care about the whole "real" or "fake" fastback thing(I am far from a concours guy as you could get), from my point of view, its a shame to see another coupe sacrificed at the altar of the fastback. That being said...if you are an experienced welder(or even if you are not, as long as you have the drive) its not that difficult of a conversion for 67-68(more difficult for 65-66). I think I would still opt for a fiberglass body on a roadster shop chassis though and spend the time on fit and finish instead when you are talking about a budget of 25k+, since originality isn't a concern....you could get more for less.
I know some people like ponies and there's nothing wrong with it. but... don't look @ it as a sacrifice, think about it as to be reborn in the better brand new body.

This pony would end to be part out because all the rear is rusty and has to be removed. A pillars are rusty through and etc.
Basically I had a choice or buy all the same structural parts for pony and spend same amount of money or buy Fastback body.
I like Fastback 68 and always wanted to make a car with a racing attitude. I said, this is extra 20k I can spend in developing this car.
So ~5k for the coupe with a clean title + disk brakes in the front, dash/tranny/engine - working. good bucket bimmer (?) racing seats, drivable no big issues but rusty-dead back/roof/pillars that has to be stripped plus ~5k for the Fastback body parts (see the expense list above).

So 10k total for the base -> all the labor - my hobby time. I'm saving her, not killing.
 

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Discussion Starter · #34 ·
Did you use silicone between the carb and spacer?
I did put it on the edges not inside to avoid any air leaks/ same high temp gasket maker ppl use on the valve covers and oil pans when no gaskets around. my tahoe running on those last 250k miles. not good for these engines?
 

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Just some guy
67 coupe, 69 Sportsroof, 86 hatchback
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Rule of thumb is not to use silicone RTV anywhere where it will come into contact with gasoline or the gasoline/air mixture as gasoline attacks it. It will wrinkle and shrivel up somewhat like chewed bubble gum. Also be nasty and useless. Permatex makes some non-hardening sealers that do work with fuel. "Aviation" sealer in bottle with a brush in the lid is my favored version for coating carburetor base gaskets. Among other things. It's not good for everything, just like silicone isn't either.

How was the roof of that BMW repaired?
 
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Discussion Starter · #36 ·
Rule of thumb is not to use silicone RTV anywhere where it will come into contact with gasoline or the gasoline/air mixture as gasoline attacks it. It will wrinkle and shrivel up somewhat like chewed bubble gum. Also be nasty and useless. Permatex makes some non-hardening sealers that do work with fuel. "Aviation" sealer in bottle with a brush in the lid is my favored version for coating carburetor base gaskets. Among other things. It's not good for everything, just like silicone isn't either.

How was the roof of that BMW repaired?
Thank you for the advice, good to know.

I placed it on the outside a bit so it probably won't be affected, but I ordered bolts with original gaskets already so I will strip it anyway.

It was too heavily warped I got a donor shell.
 

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Sounds like a great project. I'm looking forward to seeing your progress. With the rising costs of fastbacks I don't blame you for the conversion. Plus there is a tremendous amount of satisfaction out building something instead of buying something.
 

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Discussion Starter · #38 ·
I couple weeks later still waiting for the last piece before to start cutting the car.

So far learned a few techniques how to cut the car. One of the most efficient ways was done by PowerNation. They weld metal profiles to keep the structure in one piece then start slicing it.

Makes sense I probably will do it too for some parts but will have to cut A pillars unfortunately, they rust through.

While I am waiting for parts which can take a while, I decided to upgrade engine + transmission + front suspension (to fit bigger block).

Not sure which engine + transmission to get, I just know it should be 450hp+ with an ability to upgrade by adding supercharger/turbos later on. Definitely 5 or 6 speed manual transmission with override. Tranny should be small enough so I won't need to cut the car in the middle. Would be great to fit engine + tranny into $10k-$12k budget (it could be used in the worst scenario).
 

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Discussion Starter · #39 ·
Today I replaced old sparks that probably were running for 50k+ (or 500k?) miles.

Engineering Gas Auto part Cylinder Machine


All the sparks were dry but area around (as you can see) had oil on it.
It's not okay on modern cars and I guess on the old ones as well so I think valve cover gaskets are leaking unless there's something else which I am not aware of due to luck of knowledge of such cars.

Now car runs on NGK. Starts like a charm, running no hassle (no more power loss). Good.


Humming noise doesn't go anywhere but I am almost sure it's coming from rear hub.

I guess I will ask someone to drive it a bit to confirm that the sound comes from rear (so I can observe from outside) or put car on jacks and start/run it a bit to see if the sound will be there. If it's gears in the rear hub then the sound should be there no matters what.
 

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I've seen a few vids on coupe to conversion projects and you guys are double tough. There's no way I'd even consider this type of build. Good luck on your endeavor and looking forward to seeing your progress.
 
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