Passenger wheel arch.

This panel has proven to be much more tricky than expected. Cutting out the old dented and hacked up arch was difficult because of the number of welds tacked along the wells and the stringers. Since it's a much bigger panel than I've dealt with to date, it is more difficult to trim it to size. I've drilled a few holes in the panel and I'm using screws to hold it in place while I fit and trim. I'll fill the screw holes with the welder later. It's the only way I see to keep the fit consistent. It also makes the process of fitting it slower. I'm having to attach, mark, detach, trim and attach over and over again as I go. Welding and grinding is also a concern because the heat generated will be more conducive to warping of the metal. As of right now, I've cut out the old section and was pleasantly surprised at the lack of cancer (rust) behind the panel. Even on the lower edge, where it's usually pretty nasty in these things, there is little but surface rust and dirt.
I'm now a little afraid of the rear corner I'll have to replace. It seems like a much more complicated fit than this arch. My original plan was to do the corner last but now that I'm working on arch, it seems that It will be smarter to get the corner in before I do the vent and arch on the other side.