Hi Steve. I now have the Fairey overdrive returned with my rebuilt gearbox. The unit was stripped, cleaned and rebuilt with a new main bearing. It was fitted to my SIII by the previous owner and, as stated, it worked perfectly well but I felt it was rather noisy. I'm told it is serviceable but a bit worn, as you might expect. I've had higher ratio gears fitted to the transfer box so no longer require the overdrive. Are you (or anyone else) still interested in it? I have a digital copy of the manual. Regards, Nigel.