ORIGINAL: Coopz

I bought a SH .21 engine for my car, (this type) idiot me did not check the crank and to my displeasure found it to be the older OS type of shaft.
Now the clutch nut fits but as its to short the clutchbell does not go on. I bought 2 clutchnuts with a thread extender/adapter on them from the LHS (neither had the size advertised so I bought both) yet both don't fit (they are to narrow).
Then someone else told me you cannot get extenders in that threads size.

I'm totally confused, never had this problem, tempted to throw this perfectly good engine in the bin and just buy a SG shaft engine...

Any help welcome.