You've got it. The rings are very lightweight, but brittle. Using a small screwdriver you can gently bend up the rear lip, working your way around tbe gauge in very small steps. Again, they are brittle so gentle is important to avoid cracking. They smooth back nicely on reassembly and that edge is hidden against the dash.
So I pick up the clock first. We have the clock nob coming threw the glass face and the power terminal attached on the back. Am I correctly guessing that the power terminal unscrews from the back and the whole clock assemble stays on the glass face?
If that is the case I still need to remove the knob to gain access to clean the glass and possible decal the clock face. So how do we remove the knob?