I'm getting ready to do the same thing on my '35 fordor sedan, so I am all ears on this one. My rear window is fogged up in about 1/3 of the glass area and I need better visibility for safe driving. I had the garnish molding off but the perimeter of the glass seems like it is bonded in place against the opening in the body. I would prefer not to break the original glass so it can be used as a pattern to cut the new glass.