[Woodchuck]

If you cut out the rusted area to the bottom, exposing the drop off, you can rosette-weld the patch panel in place at the bottom and then cut and stitch at the top using the 3" cut-off wheel technique. Cut a couple inches through both panels, at a 45* angle, then stitch 3/4" or so toward the end of the cut, then go back and cut another couple inches, and repeat. Before you go stitching the new cut, go back to the farthest stitch and add another 3/4", and so on.

 

[JohnnyK]

Just to add, maybe things have changed, but the lower quarter patches I tried to use 20 years ago weren't anywhere close to fitting. Maybe not relevant now.

 

[Lee T]

That whole area is visible on the inside if you clean it up, then you will know how far up you need to go. Its actually more important how far you need to go on bottom side.

 

[j persons]

100 1/8" Cleco clamps are $70 and the pliers are about $9 at pegasusautoracing.com You also can get fewer Clecos and the pliers at most vendors that cater to FFR builders. I think I bought around 30 for my FFR build. With most sheet metal projects it will probably take no more than around 20, depending on the size of the project.

 

[Machspeed]

OP, you're probably going to find damage to the inner fender too. You should also know, if you don't already, that straight sharp corners are not a good idea, as you will get sink in the panel at that junction. I learned this the hard way when I welded in new fender wells on my 86 F150. I can talk to you about oil canning too....not fun!

I am in the process of a similar repair on my 69 Mach 1 that has damage on both sides of that lower rear qtr area, however not near as extensive as yours. In fact, it wasn't even noted until I had the car media blasted, at least not on the passenger side. Anyway, I repaired the driver's side with a crappy patch panel that I bought some time back from CJ Pony and had to rework the underside of it in order to replicate the OEM piece. DonP has pointed this out in his post above. Some are okay with the incorrect underside contours, I am not. On that side, I also had to rebuild part of the inner fender and mate that mess together. That was not fun. I'm not totally happy with it and am seriously thinking about cutting it all out and re-doing it.

Since that time, I have bought another patch panel from NPD for the passenger side, made in Canada (Spectra), and it really comes close to the OEM curves. At least this one does. Still, I have much reservation in cutting out much of that panel. I've cut out a small area and even have a patch made for it but it would just be a whole lot easier to remove more, fix the inner fender area, clean up all the rust and weld in a portion of the new patch. The more I think about it, the more I think that that is what I'll be doing. Good luck in your project and keep us posted on your fix.

 

[Lee T]

Yes rust around the wheel opening is very common, mostly because of the foam that Ford put in there. I suppose it was used as a sealer, but what it did is seal the water in.

You might get a good idea if you look down on the inside of the quarter at the wheel house juncture, that trash build up is also a big contributor to the rust issue. Water comes in when you wash the car, or it gets rained on and keeps the crud wet.

 

[Napaguy]

If I recall correctly the lower quarter patch shown is more of a "cover" that would go over an existing rusty panel. Think of it as a "cap". This only applies to the patch shown in this thread. I would look at other alternatives