Urgh - someone did not disconnect and reconnect the wires correctly. BMW MINI perhaps?
It is really strange how you say you have this rattle, and if you change the gearbox, flywheel, and other parts it still exists.
To me this would tell me that the part rattling is something else? Is it metalic?
Perhaps it is some other motion related mechanism - bearings, cv joints, etc. etc.?
I have a problem with my suspension/steering at the moment and can't find out what the problem is. My approach is going to be to strip it completely and replace any item that appears to be worn abnormally. - I think...
Cheers,
CSW.