Re: SS-235 with twin 4 cylinder Mercs
I have one, 1974. In mine, the engine housing extends all the way across the back on both sides, and actually makes a really comfy bed/sitting area. I am not sure if it is original, but under the cushions there are compartments on each side of the motors that are about 1' wide. 3' long and 2' deep that can store an incredible amount of stuff. If the compartments weren't there, you would have room to walk and work beside the engines. On mine, I simply slide up on the cushions on my knees to work lines, net fish, etc. I would rather have the sitting/sleeping space than the deck room.
I didn't think I had a picture handy, but here is one I took last weekend of the side of the boat that catches one side of the motor housing and cushion: