This close up of the bridge and command center shows several areas. Note the little hand wheel in the lower right corner of the photo. I put 44 men on board, the same number of troops as the crew of a Type VII C U-Boat. It's crowded.
Since my goal was to make a sub interior but not spend any money, and not spend two years on it, I glued all sorts of parts and sprue on the walls and floors of the hull to make it appear like a crowded u-boat interior.