So, I'm a bit baffled on removing the trim ring on a 1952 Ford car. I can remove the screw at the bottom of the trim ring, and the trim ring rotates...but that's all. Do you have to pry the ring off, should it pull off at some point when you're rotating it?
Some of the 1952-53 ford headlight tri rings also have a little hook arrangement at the top of the ring. Just pry at the bottom of the trim ring with a flat blade screwdriver, and it should pop off.
Pry the bottom out and push up on the ring to disengage the top. May have to wiggle it side to side as you push up.
The outer painted ring is slightly "peaked" at the top, and as @nickthebandit states, is held at the top by a hooked clip. Remove the bottom screw, pull the ring slightly out at the bottom and bump it up with your palm. Should pop right off. The inner stainless trim is held into the outer ring by 3 triangular shaped SS clips, equally spaced.
3 ss retainer springs that never go back in right when you weld Merc or Ford rings on fenders to french the lights. At least my hands can never get them back in.