Try to find the spot where the photographer was standing.
Aviation Cadet William O’Brien Mally (standing second from left). Mally, two other cadets, and their two trainers (wearing officer hats) in front of their Beech AT-7 Navigator twin-engine trainer. Mally trained at Mather Army Airfield.
Could well be the AT version of the C-45.
Photo is very thin and it is impossible to see any "astrodome" on top.