Okay! Latest version, incorporating many of the latest batch of suggestions. I've also reworked the engine rooms for different turbines, which I've censored as the parts haven't been finished yet!
If you are only going to refuel it once in 30+ years does it matter if you need to do a little cutting ? (as long as its not to complicated)
The thinking is that there will always be maintenance work that needs doing...or perhaps there will be problems with a reactor.
Could you not put say the GTG (in a raft/box) on top of the reactor and crane it off in one piece when it comes time to refuel ?
There is space (assuming I cut through the decks) but I'm still concerned about the exhaust arrangements.