I haven't had real good luck heating tint. My heat gun is pretty serious though so maybe a lighter duty one would work. If you're a pro you probably know the point in which the tint will get pliable and where it won't bake the 2 layers together. :LOL:
A tip a guy showed me was to spray soapy water over the outside of the window you're wanting to tint. Lightly rub a squeegee over the tint and this will help the tint form to the glass. Use the edge of the squeegee and push the tint towards the weatherstripping. Go 1/8" or 1/4' past where the tint contacts the weatherstripping. Use a new or sharp razor blade and cut the tint. Now you can put it on the inside of the window. You use the soapy water again and start in the center and use the squeegee to work out the water. Use the squeegee edge to push the tint up to the weatherstripping. Once you get it where you want it, trim the tint. This guy liked using Joy brand dish soap.
It is a rather big pain in the rear but can be done if you can find some patience. :LOL: