On the contrary, I'm not assuming anything. However, your reply is full of "suggested," "believe arose from a misinterpretation," "assuming," "enables us to assume," "as we've just seen there's not enough space," "wouldn't correspond," "Apparently," "could stand for," "find it hard to believe that," and other such language. I just think you're overanalyzing visual evidence that is contradictory at best, and at worst is meant to provide a wonderful canvas for story telling, rather than detailing the floor plan of the ship. Don't get me wrong; I'm admiring the work you're putting into this immensely, but I think you're allowing your assumptions about Deck 3, 4, 5, etc. to bog you down. The numbers on the doors could simply be "comm numbers" for the quarters (as suggested by 3C 42 being on the side of Kirk's command chair).