Really, they actually line bore 400 block (and clearance block for all the throws) to fit a 440 crank journal? That sounds way too costly than turning a 440 down or even buying a cast stroker crank. You think you can build a 451 stroker that will bust a cast crank? Challenge round......! Think about what goes into turning a 440 crank into a 451: Turning down the journals, turning down the counterweights, then balancing the whole thing. What you have left is a 50 year old crank that has hours of machine time on it and takes fillet main bearings ($$) and needs $$ in tungsten to overcome the weight taken out of the counterweights. And if you sunk all that money into a cast crank instead of an old forged piece...? You would be money ahead with a purpose built stroker crank, cast or forged.