Hi Dan, pooldv,
I did shut off the fuse at the garage panel, and felt comfortable taking the light out now, but just couldn't get enough leverage to unscrew the housing, and decided that I'd take my chances that it wasn't that bad in there. I know I'm taking a risk that there might be algae in there, but since it was so tough to get it out, I'm pretty confident that it's water tight enough...
My SLAM is just about done, I'm hoping to pass the OCLT in the morning and will let everyone know and post new pics. The pool looks phenomenally clear, and more importantly, the filter is holding a fairly constant pressure now, meaning there is less algae clogging it up. My clean pressure is 16 and after running two days, it only climbed to 19, which was amazing. For the past year, I'd go a day or less before it would hit 32, so I'm thrilled. Now, I'll never let the FC get low again, will stop using pucks which raised my CYA to 120+, and won't be listening to the pool store anymore.
More to come, thanks all,
Jeff