89GMCJOHN
I'm Awesome
I just went through this on my 1989...I swear I think the tint was 30 yrs old -purpled , bubbled here in the Fl. sun etc etc...I bought 100% ammonia from the grocery store...sprayed heavily on the widow then covered it with saran wrap ...let it sit for about 15 minutes then the fun began ...scraping it off with a 4" razor blade.... I did the dousing at least 2-3 times on the stubborn spots and it finally all came off .....in the end I left no permanent scratches on the glass which I was very surprised.