Ted Striker
Foot's on the other hand
If the Snap Ring (31) is still on you're fine. If that's fallen off it's almost certainly broken as it's a very tight fit that needs two small screwdrivers to lever it on and off. No tools are needed for 32 onward.
Turned out I had rotated the locking thingy (part 34), and the whole of the 32 ensemble had come off. Was a really awesome sense of discovery to follow the docs and fix it meself and have that "I now know something I didn't before"
(Can no one quote this in case I come off on Saturday and I have to edit my confidence !)