I have an 89 Pacific Coast for sale. Last year I had a for sale sign taped on the inside of the windshield. It was the blue painters tape. When I removed the sign, the tape removed some kind of clear coating on the inside of the shield. It looked a whole lot better so I removed the windshield and used tape on the inside to clean the whole thing. It looks 100% better!! Who knew?
What was even more interesting, is duct tape did not remove it!
That's certainly worth a try. Thanks.