So I took a wire wheel to my pinch welds under the rockers and I am not liking what I see, I have read alot of threads about rust problems on FC's and mine doesn't appear to be as bad as some I have seen, however I would like an expert opinion on the extent of the damage on mine and some possible repair methods.

Thanks

 

i had this problem too. it was easy to fix.. i took my wire wheel and got it down to metal so welding would be easier.. i got most of the rust off and went to Lowes and bout some steel "L" bend plates that were pretty thick.. i just put it next to the pinch area from the inside and marked where i had to cut it.. then when i got it the the right height, i just placed it on the inside and welded it to the chassis and the old pinch area.. i used a gas welder.. and after that, i just sprayed it down with some underbody coating.. thats all i did

 

I am mainly concerned about preventing the rust from resurfacing so I would like to clean as much of it up as possible, however it is very hard to get rid of all the rust from between the layers of metal? I am hoping that if I clean it up as best I can and use POR15 to cover it then weld on a U-channel to cover the joint and then seal using an aircraft grade sealant followed by asphalt undercoating it should be good for a LONG time.

That might even be a little overkill...

 

What he said ^. Better to have it done right than twice.