Whats better,grinding a crank or line boring?

Like 'Tech said... You have to machine more than just the journals or just the mains. So the best way out IMO is to get the 3.75 stroke B wedge crank from 440Source and make sure it's good. Then drop it in. If you started with a forged factory crank there is a chance that it will drop in with minor clearancing and large counterweights. I had one do that. But it's not too common.