Dick-
Since the model is going into a museum, one needs to be accurate in the description of the airplane. Your model is not an AT-6, it is a T-6G. When the Air Force was split off from the Army, it became the USAF and at that time all the prefixes to the trainers (PT,BT&AT)were dropped and they were simply called T-XX. The T-6G's did carry a TA number on the side but that had nothing to do with the old AT-6 designation. Since the model has USAF on the wing and a TA number, it has to be recognized as a T-6G.
Don, An old T-6G crew chief. (TA-223, Minn ANG)