Inspecting my 54 year old fuel tank (3100 5-window 1953) I found an amazing heap of rust and dirt in the tank. I have cut off the welded (flensh/) and clean the 2 parts. Will mig-weld it back together and put some DEOX-C in it. Having a possible leaking tank behind your back seems to me an unacceptable risk! Of course I will "pressure-check" the tank before reusing it!