Just noticed though - 'barred' waist windows. The B17F, and certainly 'Belle', had open waist gun positions. On the ground, a metal panel, with a small window central, could be slid across into the opening, but in combat, the 'window' was open, with a retractable deflector plate forward of each opening. Glazed waist positions were first introduced on the 'G' model, at first 'barred', then 'greenhouse', then 'plain' plexiglass, with the 'K' mount for the .50 cal gun. Radio room upper hatch and gun mount was normally open also.
Still looks good though !