[cdnus]

If you are convinced the panel needs replacing, I suggest
1. remove the rubber bulb 1st. leaving the panel undisturbed.
2. make a narrow template ( 6" wide?) out of bristol board to fit the contour from top to bottom.
3. transfer that pattern to a strip of aluminum (6" wide?) & check for fit in fender
4. once you are sure it fits correctly, line up & pop rivet to existing panel.
5. now you can remove the original panel with the correctly fitted repair strip attached securely & you have a perfectly fitted patten.
6. clamp onto new sheet & use it as a exact guide for rivet holes etc.

Have fun

Craig