[FatBoy]

Hi Rick,

I think you are making the same observational error that I made in believing that the inner diameter was a separate smaller bush. I don't believe it is. It appears to be the remains of a counterbore in the pilot bush. The OD of the bush appears to be standard. I'll measure the ID of what appears to be the counterbore when I get home.
The bellhousing had been centred by SA and the numbers are still written on the face of it.
I'll try to measure the free play on the input shaft as well.

Paul