Since the non-signal backing plate is common & useless without glass, there's no point trying to save it. This cutting wheel gently removes the plastic without stressing the glass. Since the silvering is on the other (viewing) side of the glass, small nicks on this side won't affect it.

After a few seconds, I was covered in black powder, so I finished the job in front of a squirrel cage blower.

Owner caption April 2012 · Photo 4365 of 5000