John,
The old school idea on this is to pack the pilot bearing recess full of grease, totally full of grease.
Then slide a spare input shaft, or perhaps a clutch alignment tool, in the hole and start pounding.
With no place for the grease to escape, the theory is its compression from hammering will act as a hydraulic force to push out the only thing that will move - the pilot bearing - or in your case, the adapter.
I have not personally needed to try this out.
But have heard of it working for others.
Good luck.
Larry
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