if your going to use stock internals, then at least take the rods out and grind all the casting flash off them, then take the rotating assembly out, crank, rods, pisons and get it dynamically balanced. once thats done you can reassemble using good bearings and rings and the short block should be good to go. if your using the magnum block the heads oil through the pushrods. get a heavy wall hollow pushrod to make sure they don't bend or starve for oil. i like the magnum heads other than intake choices that are available. with a carb its hard to beat the M1 single plane intake for a high revving engine. also definitely regrind the cam as was mentioned and you should be pretty good to go.