I think perhaps we have lost sight of the actual set up of the complete assembly Grumpy.

The inner clutch half is secured to the engines PTO with a grub screw directly on to the PTO and the other securing the key in its key-way. It also contains the thrust bearing.

The other clutch half containing the clutch cork, spring and clutch cone is secured by the 3 retaining screws placed equidistantly around its circumference.

The clutch cone slides on the engine cutter shaft with a key-way, and a woodruff key inserted in the shaft itself.
That shaft is fully floating and only held in position by the clutch cone and cork in the outer clutch half.
Any wear experienced (or misalignment) of the cork could cause probs and in a way is (by virtue of its design) a contributing factor in misalignment issues. wink
Just food for thought and all good stuff!
cheers2

Please do not PM me asking for support. Please post your questions in the appropriate forums, as the replies it may receive may help all members, not just the individual member.
Kindest Regards, Darryl grin