PBY-5/-5A bow turret

[catch 22]

Certainly, the early turret had the removable top panel which is held in place by 4 over centre clips with the hatch removed completely to the inside of the aircraft or outside on a lanyard.
As to the eyeball turret, logic would dictate the it must have still had a removable top panel for ease of mooring and continuance of existing operation procedures

BAJ, thank you for the prompt answer!
I'm sure this is the real case, but I still have my doubts that a removable top of the eye-ball turret could only be the steel one (like in the photo above). The spherical plexi top from the first photos and scheme I posted is IMHO not removable or at least not fixed with clips, but bolted.

i've always wondered what that "wash board" looking panel just under the turret was for.

Tom, the "washboard" are the shutters covering the bombardier's window. Later models have a triangular one, the earlier type was rectangular.