Richard and Joe:
You say you are novices at this kind of research, but it seems to me you've done quite a bit already on NC2072. Good show!
Allow me to introduce myself - 39 years ago I published one of the first detailed articles on the 12-A (Journal of the American Aviation Historical Society, 1974). Bill Larkins provided most of the photos, and I assembled the story and production list and tried to make some sense of it all. They may still have copies for sale. Try
American Aviation Historical Society
That article is badly in need of updating - I'd like to stay in touch with what you discover and bring the story back to life. In case you didn't know, at the time of Pearl Harbor, the 12-A had outsold the Twin Beech by 2:1, and Lockheed still had unfilled orders for the Netherlands military (model 212, roughly equivalent to the AT-11). But Lockheed was rapidly growing with work on Lodestars, Hudsons, Lightnings, Connies, and a hush-hush jet project. The War Dept. and Lockheed agreed to terminate the Model 12 and transfer the unfilled orders to Beech.
Tom / barit1