Just got one ready and dynoed. Using 440 LY rods, and cutting about 1/4" from the outer edges of the counterweights next to the main saddles with a fly cutter. Turned out just fine. I used KB "quench dome" pistons for that application, cut the domes down with a lathe, and the crank balanced internally. Nothing special in it, Comp XE275HL hydraulic flat tappet, RPM intake, RPM heads and a 750 Edelbrock AFB. Factory electronic distributor, Hooker A-bode fenderwells + 3" exhaust with mufflers. Made close to 500 hp