Re: 3 engine rooms in the TOS Enterprise's engineering hull?
"...but it is at the Engineering Station and seems symmetrical..."
And according to Michael McMaster's bridge blueprints (I believe these are based on the original production sketch I don't have with me right now) http://www.cygnus-x1.net/links/lcars...ge-sheet-1.jpg
the bridge console for navigational control would be adjacent to Spock's console on the opposing bridge side.
I'd be expecting at least one of these screens of the engineering station to display the power distribution aboard the ship.
"The first duty of every Starfleet officer is to the truth, whether it's scientific truth or historical truth or personal truth! It is the guiding principle on which Starfleet is based! Jean-Luc Picard