The repair panel I bought from Janez Kesmah is big. It consist of a large area of the inner fender shape. But I didn’t want to remove too much existing original metal I cut out the rusted area carefully and tightly.
Also, there is a gutter part in the inner fender that is not present in the repair panel. Because I liked to keep the repair as invisible and original as possible, I decided to cut around this area. This is the line just above the circular pressed reinforcement. Luckily this part of the inner fender of the car was not yet affected by corrosion.
After some cutting and fitting, the welding could begin. I decided to weld the panel in, instead of overlapping part of the new panel with the remaining metal of the inner fender. But this turned out to be quiet tricky.
I was warned to weld the panel very carefully on a low(ish) setting, because the sheet metal is very thin. It turned out to be really tricky to weld the panel in. When I welded a few spots, and used a copper backing plate to diffuse the heat, I still blew a lot of tiny and bigger holes in the surrounding old metal. But by filling the holes patiently (a friend of mine calls this “nitting”) again, I managed to weld the pannel in.