Got the car back from Goodyer's and they replaced the transfer box oil, both diff oils, have cleared the fault code for the airbag light (looks to be a faulty resistor somewhere in the loom!) and topped up the swivel pins with more grease.
Weirdly there is no play whatsoever in the swivel joints themselves, but they are leaking. I asked if a seal kit would fix it and they said no, probably need to strip them down and rebuild them at some point with new internal components (shims, pins, etc) - does that sound about right?
Also, the cruise control fault appears to be with the vacuum pump, but that is buried under a myriad of LPG related ****e so I told them to forget about it, I'm not made of money damn it!
Still, car seems to be running smoother and Graham did say it is one of the nicest Classic's he'd seen and driven - result!
Not sure what is next in this ongoing project to be honest. I want to sort the sunroof and rear windows out so probably start on them, then I guess I need to crack on with designing and building a storage system for the expedition, and sourcing a roofrack and roof tent.
Incidentally, anyone know the best place to get hexboard from for the storage system?