Kevin, I’m in the process of doing the bodywork on the fenders from my 50 F1 Ford truck. There are a number of areas in which I am removing badly rusted metal and mig welding new sheetmetal patches to repair the missing pieces. My question deals with making sure that I adequately prep both the new metal patches and any ‘doubler’ material behind the patches. Most of the rusted areas are areas where a second piece of ‘bracing’ material was behind and obviously nothing was used between the two pieces of metal and over the years, moisture got in and the rust ensued. I have been using a copper spray paint from Eastwood to the patches and using the rust converter to the braces behind. Once welded in place, I generally have no access to the space between the two pieces of metal but plan to seal the backside with a seam sealer. Do you have a general plan you could advise me for these areas? I just want to try to protect these spaces as best as possible. I much enjoy your cornerand advice. It’s been very helpful.phil.