Shoot from the hip.
Patrick,Cut a mounting hole on the stbd side of the seat back just fwd of the aft cabin bulkhead (similar but opposite the engine controls). Run the cables through a hole in the aft cabin bulkhead cut just behind the control unit. If you are like me I sit on either the right or the left but hardly ever in the center. You will have a 50/50 chance of being able to get to the buttons without getting up. If those odds are not to your liking, buy a remote control for the port side.If you ever get around to a complete integrated Autohelm system, then you will go nuts trying to get all those cable into that pedistal. I speak from experience.