If the cutlass bearings were made accurately it could matter a little but if the shaft feels tight and is not rattling then I would not worry about it.  In my experience there is sometimes more than 3 thou variation in the new bearings I buy,  not sure why but put two new bearings on the same shaft and one is likely to be tighter than the other.   Interestingly my boat came with a spare cutlass bearing and it was also a fractional size yet the shaft measures 35mm exactly so I am not 100% sure of what bearing is actually in my boat now.   

James