I can't recall for the life of me what I used to get this off my car previously. I used gasoline and a rag today, which did remove most of it, but I'm wondering if there's a better way!
If it is really stuck on there you can use Mineral spirits or paint thinner NOT LAQUER THINNER that takes off paint! But Mineral spirits and paint thinner are good for breaking up glue and other adhesives. I have done this before and also on my windows when I removed tinting works great just wash the area off good when your done and I put another coat of wax on!
I wouldn't reccomend either one of them. Eventually the mineral spirits or paint thinner will do some bad things to the clear coat. Same goes for Goof Off or any other kind of adhesive removers. Bug and tar removers are completely harmless to clear and color coats.