Have any of you guys used one of the pre-cut window tint kits? Ive had good luck in the past with them but have never used the kit for a mustang. I need to re-tint my windows, but there isnt anybody on this beach that I want to do the work. Ive tinted windows before and used the pre-cut kits and turned out great. But the main thing im worried about is the back window. Because of the compound curves, you would need a heat gun. Do the pre-cut kits still need to be shrunk? Or are they ready to go?