6NZ or Series 60
I know Kevin and most others prefer the series 60, as do I. But, if you had a 6NZ in a Peterbilt, would you be better off rebuilding it with all the tricks, or find a series 60 to build and replace. I don't need yellow versus green arguments. I want an honest opinion. Cats cost more to build and generally don't get the mileage that a series 60 gets. But, which would provide the best Return On Investment.
Is this a good question?