[Ascaris]

I just finished doing mine. Luckily, it wasn't so far gone that I couln't patch it rather than having to weld in a whole new pan. Best bet is still cutting out the cancer and welding in new metal followed by painting.

However, if you aren't blessed with a MIG I have seen fiberglass repair kits for things like this in auto shops. The trunk is hidden under a carpet (or you can buy one) so if it is just a driver, you could go that route.