I found some interesting shots of the 47th Bomb Group in WWII. They were based in Italy at the time. Note the shot of an early A-26C. It has the low canopy of the early version but also note that it has two machine guns located in the nose, rather like the early B-25's had. I had not seen this before. Also note the early B model with the 6 gun nose. And finally here is a good shot of the rear lower turret maintenance.