I have another inconsistency - the height of the base of the impulse engine cowl (at the aft end of the primary hull) is higher than the impulse engine on the film set:
The grey band in the lowest part of the window onto the impulse engine reveals that for the cowl outside the ship, the arrangement inside the ship doesn't correlate.
This one isn't as bad as it first seems, FJ was aware of it, and his solution was to raise the floor of the engineering room slightly. If you look at his cutaway closely you can see where the main floor is slightly higher than the entry foyer, requireing a 'step' where they meet. But this really wasn't necessary, as the size and depth of FJ's impulse cowling is slightly smaller than it is on the filming model, which creates this problem, so this is a case where the original "correct" external spec's work better with his internal arrangement than his own (external) version! Go figure?