R&R a light switch on an older GE range hood

[quincyguy]

In order to get at a light switch on an older model GE range hood, I have to remove the front panel which has four sets of push-buttons for the cooking coils
The chrome rim around the front panel 'feels' like it can be removed with a putty knife behind it but it will not pry off.
Is the front panel screwed on from behind?
Sorry, no model number  - worn off

[Repair-man]

The plate does pop off, and is sometimes difficult to remove if years of grease have flown thru it. There may even be 2 small slots on the top edge for you to get your screwdriver blade into, but if not go ahead and pry from the top edge with a putty knife.

[quincyguy]

Hi, Repair-man
Many thanks - but - after poking around the whole chrome rim with a broad knife
I was able to separate the tabs which fit into slots on the hood.
But the bugger won't come off! When I gently pry it away it snaps back quite firmly. 
I'm afraid I'll break the glass.
Something else is retaining that thing on there, and I'm thinking it might be some kind of spring-loaded clip arrangement form the 50's.
Thanks for your kind help and the merriest of Christmases to you and all the folks on here who help others.
Jim in Dartmouth MA