Tint Removal

Hi all,

i had to remove the tint off of my car windows. luckily the tint film wasnt a big problem for removal, the problem is the glue that is left over on the glass. I managed to remove all of the glue from the side windows using nail polish remover and the razor but i am having doing the same on the back window. Is there anyway i can remove that glue without damaging the de-frost lines? i will grealty appreciate your feedback. thank you all.