In the old days, back before most of you were born, replacing the bearings without turning the crank was a common occurance. As long as you get to it before the journals get eaten up, it can be a new lease on life for a high mileage engine with low oil pressure. If your oil pressure is fine, I don't think I would do it. Now a new oil pump is definately not a bad idea. On an older engine, a high volume pump isn't a bad idea either.