One of my '88s has the purple factory tinting that was available as an option on the rear side windows and rear windshield. The rear windshield was fading and bubbling, and was getting to be really unsafe for lack of good rear vision, especially at night.

Thanks to a suggesting that I got on this board, I used one of the last warm weekends out here in Schwarzenegger Country to fix it. First of all, I took the third brake light off because you have to in order to get at the tinting behind it. Then I cut a black plastic garbage bag to fit the outline of the entire windshield, and sprayed the windshield and garbage bag (on one side) with window cleaner (the common blue kind with ammonia). Then I slapped the plastic up and stuck it onto the inside of the windshield and let the sun warm it up and soak up the liquid into the tinting. After about ten minutes, it was pretty easy to peel off the first layer of tinting. It was then that I learned that the factory tinting was actually two different layers, and it was the first layer that was the one that was decayed and bubbling, and for this reason was the easiest layer to peel off. The next layer was not in nearly as bad of shape and took me quite a while, doing the window cleaner/sunlight thing several times, and scraping, peeling and rubbing the film off as best I could. I was making progress but it was slow and tedious. Finally I tried a razor scraper tool, and very carefully experimented on one corner to make sure I wouldn't scrape off any of the defroster. As it turns out, as long as I was careful not to go too fast or press too hard, the scraper tool (I put in a brand new razor blade and things were much easier) didn't catch on the metal of the defroster and it took the last layer of tinting off quickly and easily, even in the tough areas that didn't respond too well to the window cleaner.

When all of the film was off of the windshield I used some more window cleaner and some fine steel wool to get the adhesive residue off. Then more window cleaner and a clean cotton rag, and then it was done.

If you do this you will find that it will help to have a strong vacuum nearby, because the little flakes of tinting plastic get all over the place, and due to the adhesive it sticks to the upholstery and is hard to get up just by wiping it. It took me about an hour from start to finish. It was well worth the effort because it looks like a brand new windshield after a long time of getting used to the old messed up situation getting gradually worse with time.

I'm really surprised that you were able to scrape over the defroster grid without cutting it! That grid is pretty tender and a person has to be carefrul in even just cleaning the window.

I guess you could still do this in cold weather if you placed one of those 500W halogen portable work lights on it as a heat source?

Yeah, I suspect that might work. They do get pretty hot. But how would you get it to stay close to the windshield, perhaps by hanging it from the ceiling? If you have a heat gun that might also work to warm up the glass from the outside, if you were careful and if it were on a low setting so there wasn't a risk of cracking the glass or damaging the weatherstripping.

I don't know how much of it is the heat and how much of it is the chemical action of the ammonia. You might just try the plastic and glass cleaner to see if that works without the heat.