Backyard Pool & Spa

I would explore using Jandy's AquaLink system. After many years of experience it seems like these are the most user friendly after the installation. Additional lighting or whatever auxillary functions you would like to add after the installation are also done with relative ease. There are many types and styles of controllers, and the systems themselves are easily programmed.

Definitely no problem with just an inch of additional overhang

If the unit is losing power, it is an issue within the Power Center/Control Box, not the cell itself. Suggest replacing the board inside the power center. you can put a multimeter on it to confirm it is actually losing power when the lights shut off. Careful, electricity can hurt ;P