start the truck take it for a drive, run every single accessory you can.
shut it down disconnect battery put meter inline and wait 15 minutes, it should drop,
remember most meters are fused at 500ma or lower for the Ma rating, if u saw 2 amps and tested it on the ma setting you prolly blew the fuse. check the fuse
normal ma draw is somewhere in the area of 30-40ma. you should let the vehicle sit over night and check it in the morning as well, with not opening the doors or touching anything that will power the computers back up. that said a 100ma if that is remotely accurate should not even come close to draining 2 batteries in 1 day
