Taken from an e-mail I got from Doug Lamerson.

I am curious about the source of your information about 60-3762. This plane, the first "production model" procured by the Army, served with the 536th TAS at Vung Tau where I had the opportunity to work on it many times. In 1975 it appeared here in Hawaii with the ANG. In 1978 I arranged to photgraph it and inspect its records. Its USAF 781 form showed transfer to VNAF 431 Sq. on 12/29/72. However, the next entry, dated 1/73 showed, "Air America Contract Service Weight Reduction Program." This entry was also found in the records of other USAF C-7s over the years. Consequently, I have some doubt as to whether 60-3762 actually ever flew with VNAF or instead flew for Air America until war's end. That provides one explanation for how it got back to USAF. There are many mysteries of this sort associated with Caribou operations in SEA. Wayne Buser, John Syzmanski and I, among others, continue to work at it.