The proper diagnostic procedure would be as follows.
1. Load test the battery.
2. Load test the alternator.
3. Remove the positive battery cable and insert an inline AMMETER with at least a 10A scale on it and check the current draw with everything off. Remove the underhood bulb and make sure the trunk and doors are closed and the key off. Check the draw at that point and report back.
IF you find a moderate draw over 50ma say with everything off you can pull fuses one at a time until you find the one that eliminates a current draw.
Work your way down from the 10A scale to 1A to 500ma to 200ma if the meter is analog and the needle doesn't move at the previous scale, check the digital meter as well they usually have one or two positions to use.
You start off on the high scales so as not to peg or overload the meter.