I just spent a productive weekend swapping the BW35 in my 164 for a M400. No O/drive but I recon I was lucky to find a wreck with an 8 bolt flywheel and a good box. It was a 2 day struggle but well worth the effort as the car is transformed. It wasn't cheap after getting a new clutch kit, tranny mount, pilot bearing, and master/slave kits & hose. One thing to check if you ever do this is the condition of the chassis ? rails where the tranny support bots up. The holes to mount the manual support are about 6" forward of the auto ones and there could be damage from people using it as a jacking point. Mine were the cause of much cursing and hammering but were persuaded to cooperate after about 2 hours. I am now pleased to be able to get away at the traffic lights with everyone else. Viva the 164 !