I have a 1971 SL100 that I am currently working on.  I have just finished rebuilding the engine, and was going to check the timing after running it for awhile.  When I took the stator cover off, I found that the large O ring gasket had come partially undone and had a piece of it ripped off by the flywheel.  I can't find it so I believe that it is in the gearbox somewhere.  My question is, can I remove the left side case and access the gearbox (after removing the head, cylinder, timing chain) without removing the clutch, oil pump, and everything else on the otherside of the motor?   I think the answer is yes, but I wanted to check to see if anyone has ever done this before.

Thanks!