1966 Cadillac tail lights

On my 1966 Cadillac hightop, one of the brake lights is out. On a '65 the lens comes off with a couple phillips screws, but with the '66 it has the center chrome strip that makes the single lens appear as 2 tall & narrow lenses. How do you go about changing the bulbs in a '66? I'm wondering if there's access behind from inside vs. underneath to change them before crawling under it & rooting around.
On a side note: If anyone would happen to have any of the chrome bezels that encase these tail light openings, please send a PM. Thanks!

it's a reach up and fumble around. if I remember right they have the 3 screws that lock the socket in place. darn near easier to pull the bumper to change the light. I did them with the bumper off and made sure they worked before I put it back on. nope missed that guess, checked they only have the two. no trap door. reach up loosen the set screws twist change go back. have fun. if you don't have any of the socket grease regular gun grease will work just as good. fill the socket up to keep the water out of it. the lense will not come off with the bracket in place. it has to come out from the rear. so if drop the bumper or fumble with this one. your going to hate were they put that tailpipe.

Thank you for the detailed info Ed! Complete with photos too

I found on my 66 Superior it was easier to drop the bumper, but my screws that held the bulbs in were pretty rusty.