How I wish I'd taken a "before" picture, so you could see How awful my rear window was! it say it was milky white like a frosted window, and heavily pitted and stained. Before I spent a lot of money on new plastic or full glass top, I thought I'd try some headlight polish I had.
FYI, this took a LOT of elbow grease, and is a SLOW process. I'm actually still working on it after several days of labor. I've buffed the window countless times and invested maybe as much as 12 hours bent over the rear window. But look at the results, for only a $6 bottle of plastic polish!