VR,
All headlights and mounted taillights run off the 12V. The Lightman strobe uses 2 AA.

BTW, has anyone ever seen anything like a standard 12V plug (car cigarette lighter type) that has threaded cover for watertightness? That is, the female has exposed threads around it, and the male has a threaded cap and O-ring to snug it down and provide a weathertight seal, but you could still use a regular male plug without the threaded cap? Even though there are smaller plugs, I like to stick with this type of outlet on my battery box so I have the option of plugging in other accessories if I need to, say, for instance, a car charger for my cell phone. I have seen female 12V outlets with spring loaded covers and males with a seal. I guess that might be the best I can do. Right now I just have pretty standard outlet and plug, and I have a "rain cover" of heavy nylon Cordura over the battery box and plugs to keep rain from hitting anything directly. It has worked fine, I just keep looking for refinements.