with everything off, pull a batt cable (either one) off of its' post at midnight & see if you see a spark (that'll tell us if there is a draw & is there a clock, or stereo light or anything lit up inside at night with key/lights off?). With it back running at a fast idle check voltage at batt terminals and at the blue wire terminals at the alt and reg and the alt "batt" terminal. that'll get us started