I started to work on my C80; however, haven't completed it yet. Seems to work OK, but a very lengthy & tedious process, polishing manually. Going to search for a small bonnet to attach to a power drill to speed up the process. Interestingly, I watched a You Tube video on replacing the glass screen. Apparently, there is a plastic protector that covers the glass screen; therefore it is the plastic protector that we are polishing; not the glass screen. My searches for a replacement plastic screen cover have been unsuccessful.