Taken the engine/gearbox out again, to solve a few problems. Engine was burning too much oil. probably glazed cylinders caused by too rich carburettors during the running in period, also oil leak between bellhousing and gearbox. I'm getting quite experienced now in taking the unit out on my own, the key is patience and preparation. I use a trolley jack under the cross member, remove front wheels to create more clearance to get the unit over the front of the 122S, slowly lift the unit and push the car back. The fact that I have a removable gearbox tunnel is a plus. I can remove the driveshaft bolts from above and support the gearbox from the top (hanging from the floor) while removing the gearbox support underneath. Tomorrow I will deliver the engine to the engine builder, I can't wait to find out what the problem is.