[projectRDM]

Razor blade and Windex does the side windows quick and easy, I worked at a tint shop for a few years. For the rear, we used a chemical degreaser and a scuff pad, worked well enough in all applications. The above does work better but I didn't always have access to a heat gun when three other cars were being tinted.
I stripped a car not too long ago for a friend, the rear window was the worst I've ever seen so instead of stripping it I just swapped the glass out. Helps when you have nine S14 rear windows laying around.