How old are the rubber boots? I replaced mine when the car was painted (10-12 yrs ago?) and they're still very supple. Supple enough to not think twice about removing all four (4) beehive lenses/chrome trims for its annual waxing and detailing (if it wasn't for the All Brit Show up near Tampa, no telling how long I'd put it off...).
Replacement boots are pretty cheap, if your bulb-holders and all else are still good, and I can get my lenses & rings in with my thumb or fingernail.