Realy all you need is a 440 or 413 crank and rods then Diamond or Ross pistons. Flat tops are ussualy on the shelf but pop ups are custom. Check with the piston manufactuer before you bore. I belive they will be a .035 overbore rather than std..020 or .030, .040. The crank would then have to be cut down on the counter weights. Which makes for a lite weight rotating assemble.