I just picked up an 88'SS that I will be parting out soon, very rusty. I did notice the t-top glass has this stamping on it, same for both sides. This is an original CC1/t-top car and the car is mostly original so while I assume these are too, not sure. My 87' and I think other glass that I've noticed doesn't have this stamp but then again I don't check them all, just caught my eye. I thought I'd see if others with t-tops have this PPG solarcool stamp or something different, maybe it was for later 87's or 88's only, or replacement glass? Or many are and I just never paid attention.