The one place I’d argue is that, where do you find a stock as delivered 340 from ‘71 & down with the high compression pistons till running around today in good shape?
I think it’s a load of bologna because (IMO!) they all need to be rebuilt.
i was assuming that one would be starting with a 10.5:1 bottom end on a fresh build and then working toward 400 from there, not slapping parts on a wore out 55yr old motor.