Last year, I had my car's tint stripped becasue I wanted 5% limo tint all of the way around. Anyway, I asked the guys how they removed my old tint. The sparayed all of my window's old tint with ammonia and then let it bake in the sun for 4-5 hours. After baking, the old tint was easy to remove. The said the longer you let the ammonia sink in and bake, the the less likely the are to scratch up your windows removing the old tint.
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