I see the ant wire leaving the reel on the left and going downward, does it have a phenolic tube with the RF connection on the end passing through the fuselage like the B17?  How well was the handle insulated, considering they might be turning it with RF applied looking to peak in antenna current?

I had a Navy instructor in 1971  who at one time who was a crewman on a  PBY's in Atlantic Ocean patrol zones during WW II and said the big problem with the single .50 cal gun mount at the blister, was the the casings would come back and hit you in the face, leaving little red marks from the hot metal. That became sort of a badge of a PBY waist gunner.  Thinking back now, in '71 that was only 26 years after WW II ended, and this man was only in his late 40's at that time.

Charlie in NC