[rich weyand]

You're doing it right, with the meter on amps and inserted between the battery and the removed cable.

Removing the negative cable is safer, because you can't touch the positive to any of the grounded metal all over the place and cause problems.

The .02 draw is not a problem. The 1.02 draw when the door is open is correct -- several bulbs (ceiling, in the doors, whatever) drawing 1 amp more.

It sounds to me like there is a circuit in the truck finding an intermittent ground. I had one of these in a van that drove me crazy. The wiring harness was pulled hard around a sharp corner somewhere, and when the temperature changed, it would short the dome light circuit. On a van you have to bulbs in the middle ceiling, the ones in the cargo area, the ones in the door wells, etc. So I would park it and when the temp fell overnight, the dome lights would turn on and drain the battery. I never did find it. Being a van, it had a defeat for the dome lights for loading in the daytime, and I just left them turned off.

So something could be "turning itself on" by finding a ground somewhere at a chafed wire.