CJ - AC does indeed have all 4 engines in place and complete. I wouldn't want to drop an engine as that would make her an incomplete aeroplane, and actually you can clearly see the compressors deep inside the intakes during tours, which is nice. She'd look odd with one intake blanked off.
Ideally I'd like a sectioned 593 on display, as there's not a lot to see on the outside of a turbojet engine except the ancilliaries - and you can see those by opening the engine bay doors.