Originally Posted by BoostedSRT
I thought it had to do with reading the VIN and seeing if the body code / color code / model code and motor code from the VIN matched the car and its model designation ..
Bingo. Numbers matching also includes correct paint an options. If you've got a VIN for a non-AC car and it has ice cold air, that car isn't numbers matching anymore. You've gotta have the correct driveline, with correct year parts, as well as correct paint and options to make it truely numbers matching.