I finally got tired of looking at it, so i took the angle grinder with the wire brush to the rust spots on my back fender. one spot broke through completely to the inner fender piece and the other spot wasnt quite as bad. I then used a cut-off wheel to cut around the cancerous spots and to further investigate. The rust spots were where the inner/outer fender meet, and looks like rocks and moisture were wedged inbetween the innner/outer fender. There was/is a piece of foam insulation in between the metal too, along with the flaky rust and, and rocks.... My plan is to clean and clean, out all the debris and rust from the inside, then give a heavy coat of primer to the inside and maybe make a couple of small drain holes. Then patch the outer fender by backing the hole with fresh sheetmetal and then use a little filler to even it out. Any body shop guys out there? does this sound like it would work? I would appreciate any advice. Ill get some pics on here hopefully by tonight.

 

Yup that will work, or you could buy a replacement aftermarket panel to fix that spot. The latter would be the way I would do it. It makes for a neater job and less work.

 

yea, cut it all out, round the sheetmetal to form to the inside of the fender. Hold it in place on the inside and weld it to the fender from the outside along the edges. Grind down the edge, fill w/bondo sand, prime and paint.

 

Yeah im gonna go the "patch" route i was working on it yesterday, got the hole cleaned out and got a patch ready im gonna weld it in today, the patch fits tight and im gonna braze it in there because we dont have a mig welder. Ill be glad when this is done! if its a good patch job ill show a picture of what it looks like and if its not i wont Heres what the hole looks like a day ago, i had to cut it bigger to clean out all the rust.