Well, unfortunately things are always worse than they appear on the surface. After some close examination of the inside of the roof skin, near the rear window I saw some rather deep looking pits. I poked at a few of them to find that they easily went clear through and made a tiny pinhole.? Doh! I guess that big back window, and the moisure-holding insulation that was against the roof skin on the inside created a situation where the roof skin would rust from the inside out. I poked away at all the deep pits with an awl until I was confident that I got them all (cross fingers). This resulted in about a dozen holes to weld shut. Knowing that this could be a disaster if I didn’t take special precautions against warpage (from the heat), I decided to try something….. I had heard about some “heat fence” putty that was available to disipate heat when welding on thin sheet metal. Not having any around I found some old modeling clay that I had from years ago… so I gave it a shot, and damn if it didn’t work awesome! I made a “donut” out of the modeling clay, and then welded the hole shut… got them all done in a short time with no warpage at all! Killer!
