Ian,
I'd PM'd you in response to yours before I saw this. Easy, four screws (from memory of a couple of weeks ago, I'm at work) and body tabs on the ends and sides. The electrics disconnect from a central terminator strip, the functions of each wire (which are pretty self explanatory anyway, apart from possible confusion between the pickups and the motor leads) is amongst the exploded diagrams in the "handbook". The lights simply unplug from the body. The buffer beam unscrews with two screws each. The cab comes away from the body with tabs which are a bit fiddly but not too hard - while it shouldn't be overdone is does need firm handling, and it then lifts off vertically on what are, effectively, rails. Windows push out (being careful of the wipers) and the sidescreens by the drivers position also unplug (as do the side overhangs of the roof) and the cab interior just pulls out - I took this all the way apart as I am repainting mine. Afraid I haven't removed or disassembled the bogies so can't help there.
Steve