Don't know if this will help, but I've just done the same to a 1990 model 215 A series
1) Take the lift to the top as far as possible after removing the limiter on the track
2) Unless you have help or can lift about 8 stone of awkward shape, then remove all the panel screws/bolts, push the wires through to allow slack & then remove the seat bolts (mine had 1 static bolt at the bottom & 2 which fitted into a runner behind a panel which come off when twisted, but the bottom nut has to be loosened)
3) Remove the top end cap & the screws which hold the wires/cable to the chair, you can hang these over the top just by pulling out as long as have enough slack wire.
4) Go to the bottom, remove the end cap (we had to take the main frame off the middle & bottom supports & raise)
5) Back to the top end, wind up the motor unit to make the chain tight, you can then lift off the chain top support, make sure the manual brake is on, just leave hanging on the top of the runner.
6) Release the manual brake & allow the unit to either slide down, or if it won't move use the emergency winder ( Stuck mine in a cordless drill) This allows the chain to slacken, allow enough looseness so that you can lift the chain over the side at the bottom end & put brake on again.
7) Put the chain over the side & you can access the allen bolt to release chain at the bottom, which is on a spring thing.
8) Release the brake, whilst supporting & push the unit up, it should then come off, put it where you like (wires permitting ) then do what you need to do.
9) I only had to do clean up & put on new wheels, so just re-assembled Got the parts from
www.stairlift-spares.co.uk based at Spilsby Lincs. but deliver worldwide. They are local to me & gave me the above guide, absolutely excellent.
It took me & my son about 5 hours, but we were only guessing on the basics given. I can only think that the mechanics will be very similar as these don't tend to change a lot with time, the electrics are different, circuit boards, voltages, etc. so I don't know anything about them.
Best of luck
Michael Digby, October 2007