What do I need to do for selecting pushrods? I have the heads and cam. Is there anything I need to do to check geometry or something, or can I just order 'standard' 454 pushrods or something? Thanks.

alot of variables to be considered you should just get one of them pushrod mockup checker thingamabobs put it in and go around couple times and tip of rocker or roller should ride in the center of the valve stem
shane