main bearings are the same for b-series motors. what you have to worry about is that the caps off your ls were line-honed to match perfectly with your ls block. once you introduce different main caps you lose that alignment unless you bring it to a machine shop who can perform an align hone on your block with the new mains. that’s why you can’t just buy replacement main caps from honda.
What would you suggest? Should I have my center ls cap machined or should I have the b18c caps align honed? Should I scrap the idea and buy the Z10 piece?
This is the last issue I need to resolve before my block goes to the machine shop. Thanks again.
since you already have the b18c girdle i would stick with that. machine your middle ls cap & also machine the other two so that they can accept the b18c dowel pins. do an initial torque down for the crank using plastiguage to make sure that the clearances haven’t changed after the installation of the girdle.