After my daughter's accident in my '62 last november, we were able to find a decent (repairable) front fender for it.
When I started taking it down to bare metal for repairs, I found that some previous owner had used fiberglass to repair the rust behind the wheel well. What a mess! I got it all cleaned out, cut out the rust, cut a piece of same thickness sheetmetal to replace it, then brazed it into place. A little lead and it will be all good.