The windshield and rear glass on my truck were broken so replacement was the only option. The side windows didn't look to good but weren't broken. There were threads going on at the time about some of the replacement glass being too thick and other fitment issues. I figured I had nothing to lose so I took rubbing compound followed by polish (made for paint) on an electric buffer and went to town on my side windows. In my case they came out looking new but it took considerable buffing. The go up and down very nicely even with all new felts and rubber.

Chuck