I have a trusty Beseler 23C and I had heard that a lot of people used to grind out their 35mm negative carriers to allow for full-frame printing. I've seen some HCB prints wherein he shrank the image to allow for wider margins just to avoid a crop. Anyway, I figure that a larger window in the holder, allowing for a full frame, can only be a benefit.

Has anyone done this before and have advice on how to do it? I'd really love to avoid destroying my only carrier for 35mm, and I'd like to avoid anything that leads to some sort of distortion, or leaving anything that would scratch my negatives.