Rear Main Bearing Clearance

[Graham Barker]

I am well into a top end overhaul of my Ruby 3 bearing engine, but did not plan to overhaul the bottom end as it was allegedly done at a bit more than 1,000 miles ago, although that was some years back.  There is a little radial movement in the rear main roller bearing. When the crankshaft is pushed to one side, I can get a 2 thou feeler into a gap between the roller and track. How acceptable is that? Is anyone going to tell me that I can happily leave it alone considering that I do not expect to do high annual mileage's, just local Sunday drives?
I have read about acceptable clearances in roller bearings when measured with the bearing in free space and 2 thou is not too bad compared against these.  I have not been able to find references to acceptable clearances when the bearing is compressed into its housing.