Engineering Top Deck:

1) Maneuver drives. Four separate roughly cubical modules
2) Jump drives. Two separate, roughly cylindrical modules
3) Power Plant. Three separate, roughly spherical modules
4) Lift shaft. This is a square tube which runs the vertical length of the ship.
    The lift itself is a 4x4 grav platform.
5) Air-lock to ship exterior, or mated to tunnel at Victoria-standard docking facility
6) Workroom containing tools and a work bench. (This is a separate workroom from the sub deck)
7) Stairs up to Fuel Deck 2 & down to Engineering sub deck (up is going down on the floorplan)
8) Catwalk surrounding all the drives and allowing access to the top parts of the drives

NOTE: For the Jump drive and Power plant, since these are rounded objects there is slightly greater access underneath and on the top than the floorplan shows (floor plan shows the rough midsections of these drives). Thus on the sub deck you can crouch, and get further under the drives, and on the Top deck you can, to a degree, climb on top of these units.

NOTE: The usual access to the sub deck is via the stairs or the lift shaft, but the catwalk does have openings at various points around the drives (seen as white gaps on the floorplan). Most of these openings allow an individual to climb up or down between the two engineering floors.