There is an official procedure for tracking down an excessive draw around here somewhere, I just gave quick and dirty cliff notes. I don't have time to find them for you right now though.

Mystery solved. There is a sensor somewhere on the dash that detects daylight, and so turns on the headlights for safe highway driving. While that is going on, there is no indicator light showing if you turn on the headlight switch. If you do, they will come on in the middle of the night, and drain the battery. Now I just need to find that sensor, and cover it up when I'm wondering if the headlight switch is on. I think this daylight sensor thing is Canadian only.

not sure if its canadian only, maybe in 92, but most every gm with that the sensor is in the middle of the top of the dash looks like a half globe about an inch

Thanks!

Actually, if there is a small dome, I believe that is the solar sensor for the climate control. I believe the sensor for the lights is on the right side of the dash, at the end of the defroster vents. Looks like a round dot. If you cover it, it will cause the lights to come on.