I have a 72' Cutlass Supreme (455) and right below the rear window has not fully rusted through, but has become very thin and brittle. There are a few small wholes that leak. I was wondering if anyone new of a way to permanently seal this area. I have heard that this is a problem on many GM "A-body" cars. Any help would be appreciated!!!

 

cut out the rust and replace with new metal (after you remove the window).