if you can get the new bearing on by hand you crank is worn ,[ no need to measure it]
the bearing should be interference fit. that why you should have to use a pullers to split the cases
if the motor comes apart easily ,[ it usual mean something is worn [cases or crank journals]
even with a worn journal a new bearing can appear tight , [as the crank is only worn slightly where the bearing spun,]
look for polished look on journal
if u rebuild engine with worn crank, may run ok for a few hours until crank starts moving sideway and damages the crankseals