Not on P-cars but I have done similar repairs with a combination of pop-rivits and fiberglass...that have long outlasted the rest of the vehicle (volvo).

 

Those are pretty much exactly the areas I had thought I needed to replace. The rust in the wheel well doesn't extend forward of the firewall but I suppose the replacement will have to overlap it a bit anyway. The bottom tray will have to extend up the slope at the driver's side and at the rear a few inches but that doesn't look too difficult.

If there was any way to do it as 1 piece that would be better although I suppose I could find another donor piece if it's really necessary.

If you have pics that would be great thanks.

 

I haven't found the pics yet. Its not possible to do it in one piece, there is no way to fit it in in one piece. You have to cut away the bad first, then replace the box section piece and the firewall pieces first. The battery bottom goes in next and then the wheel well piece "caps" it off. You have to do it in this order for fittment and access for welding.

 

I shouldn't say it "has" to be done in that order but that is the way I've found to be easiest. You're probably going to find the rust is further than you think, it tends to creep under the coating. The soft spot is where the rust hole is, the seams where the pieces meet will not be reuseable. You're probably going to find rust inside the box section as well, especially on the wheel well piece. You can use the pieces from one donor car if you can seperate them cleanly. I usually destroy the wheel well piece to save the other two and then get a new wheel well piece.

 

It's a pet peeve of mine to find unfinished threads. People lose interest in their own threads once they get a resolution. There's nothing worse than finding an archived thread from someone who had a problem just like yours only to find they haven't bothered to say what happened in the end!

So, here is the last chapter in this particular adventure: http://www.kcws.org/forum/showthread...repair-the-end

The tldr version is I had a classic restoration shop cut out and weld in the new pieces, including the wheel arch bit, then coat it in a rubberized undercoat and paint it. Pretty much factory finish, never to be worried about again. It was a ton of work, but this is the way I'd do it again if I ever had to. But I will also make bloody sure I never have to.

 

404 error. bummer. I really would like to see how you took care of this since I have the same issue

 

Yeah I'm sorry to say that site was taken down a while back. For what it's worth, that wasn't actually the last on the matter. It leaked again around a year or two later, and I had to get another shop to take another look.

TBH the thread didn't show the details of how it was done anyway since I didn't really have pics of that - just before and after, and one in the middle with the floor of the tray cut out. I wish I could give you more advice but this is a tricky problem that you need someone who's interested in it for.