As no one else seems to have bothered to reply to your enquiry, it seems you are stuck with me, again!
I`ve just drifted the layshaft bearings from a pair of D7 crankcaes, each measures up at around .002” interference on the nominal crankcase bore size of .625”. I cannot think that you could force the ones you have with that huge interference of .006” into the cases and not have the bore collapse inward preventing the layshaft from entering. You may have the option of adjusting the bore size from boring or reaming but if they are genuine sintered oilite ones then the cutting of the bore forces metal into the tiny cavities enabling the lubricant from being released thus destroying the self-lubricating properties. I have made solid bronze bearings in the past but these were to compensate for a well-worn shaft, mind you they did work very well indeed with provision for direct oil feed.
Can`t help more than that I`m afraid.