So I got one of those cheap ebay Chinese light kits, but all I used was the switch. The switch actually works really well.
I couldn't use the shaker top as the rear light. Figuring out the logistics of mounting a light inside it is pretty difficult, so I gave that idea a rest. I may still revisit that one another day. For now, I'm using 2 trailer marker lights, which are plenty bright. The headlight is really bright as well. It lights up the road so well at night, and as i ride past people oncoming, i see them shielding their eyes. It projects from about 2 ft in front of me and throws a serious beam way out. Just what i wanted.
The battery is an 8.4Ah 6volt from batteries plus. Cost about $25. I've had it on almost all day and it's not showing signs of dying any time soon. It may be a bit overkill, but I'm scared of being stranded somewhere without lights. At a 3.3mA draw with the headlight, tail light, and brake, it will take a long, long time to kill that battery. In the world of batteries, the capacity curve is almost asymptotic. So think: An 8.4A draw will last 1 hour. But a 4.2A draw may last 2.5 hours. I had a battery rated at about 9000Ah that would last 3 hours at a load of about 3000A. At 125A, it lasted for a loooong looong time, and discharged over 14,000 A!
Yes, I'll say it again. Overkill.
Of course it would rain, but it happened as soon as i got back from my 15 mile ride. It's such a pleasure to ride.
My next step is to pretty everything up and install acorns where I can, and I'm also going to redo the battery mount. I'm thinking a round brown vinyl bag with a zipper for access, maybe some white vinyl piping to match the seat. Sort of a cylindrical bag so it will match the theme of the bike and cover the battery.