MTBrandenburgB

I would bet money that the metal grille is what pops off, and the screws for the rest of the faceplate are underneath.

Source: me after ten years of guessing in my own 1970’s home.

The problem with just breaking it on an older house is that you find a non-standard mounting box or just something weird underneath it.

Breaking stuff means you have no way to cover the hole when you find out you can’t replace it with anything. :)