I have a glass holder (anti-Newton) for 4x5 for my Beseler 45MX. The bottom piece of glass (normal glass, right?) has a small group of scratches. They're barely feelable, but definitely show up in a print. I could swear they weren't there when I bought it (used), but I can't figure out how I could have made them. Anyway, should I just look around for the right glass and replace it or could it be possible to burnish them out with the right bit on a dremel? Then, if it's worse, I can buy more glass. And what would be a good source for glass that's the right size?