Well, I've finally decided to repair the rust damage in front of my rear wheel well created by the stupid trim piece capturing dirt,etc. back there and not cleaning it out until a few years ago. Last night I ground out pretty much everything I could and left a nice big chunk of metal missing. My plan at this point (since I'm cheap ) is to use a metal filler in the giant hole that has been created and then fab up a sheet metal cover with countersunk screws on top (so the door will still close) and screw in from the back for the bottom portion. Unfortunately, I need something to screw into. So my question is: Has anyone used a metal body filler that they would recommend? JB Weld, etc.?

Also any other ideas for the DIY repair would be great. Thanks.

Scott