Here is a diff. way
get a few black plastic trash bags and some spray bottle with water,glasscleaner, anything with a water base. and spray the window down and cut a section of the black bag to size and when the glass is wet enough the black plastic (only one layer thick you can cut it all up but dont need it doubled over) will stick to it. let it set in the sun for 15-45min. (depending on the heat and amount of sun) and then take off the plastic and the film peals off, now the glue will reset so you will have to re-wet the window and use the plastic agian but I did all back 3 windows of my 94gt in about 3-4hours (this is also counting the sitting in the sun time with me inside) and it was a piece of cake. GO over the window with some windex to get any glue off that might remain.