Soaked mine in some penetrating oil spray for a few hours.. i was able to wiggle the connector free. Now working on spraying and freeing the bulb. I do like the idea of using the LED bulbs. Gonna order some and give em a try.
Check the lumen output for which ones you fancy. Some put out very little, others, quite a lot. I opt for the latter, in amber/ I also cleaned out the old chrome plated fitting, and the translucent amber plastic block meant to convey light from the old bulbs to our eyes. Am pleased to see that the precise light from the LED transmitted well through the block.
Do yourself a favor and replace as many of the old incandescent bulbs with LEDs as possible. They draw considerably less current and emit light much purer than the incandescents. The SOLE exception I permit is the headlights, ironically enough. To my great disgust, I find that instead of making LOWER POWER, MORE EFFICIENT headlights, these corporations pander to juvenile fantasies, making absurdly over powered and extremely dangerous LED array headlights which blind oncoming drivers. I scored a case of old Westinghouse 4002 low beam lamps sold under the Union Carbide label for a cost of $2/lamp, then found a pair of GE 4001 lamps for the high beams. These lamps, made contemporaneously with my car within a couple years came off the lines at the peak of their quality and production. Such quality seldom can be found today, and if so, for a stiff price indeed! I suppose Hella might make a good lamp for the money, though I don't know by experience.
I KNOW the lovely pearlescent orange tinted glow of my venerable headlights flooding the road or whatever lies in front of Mathilda, at the exact wavelength specified by the United States Department of Transportation, amply yet SAFELY illuminating all within their range, shows the Cognoscenti a good sample of a Quality taken for granted, now gone forever from the land which produced our C body machines. I used #10 AWG wire running off relays adjacent to the battery to insure ample current reaching these lamps. Don't scrimp on this detail either. The old #16 AWG headlight harness wire is adequate for controlling the relays, but never was for the bulbs themselves.