zero compression yes Zero lol !

Also a trick I use to install pushrods. Get a piece of coathanger, straighten it out and slide it between the pushrods and the valley side of the rocker pedestals. This holds the pushrods out enough to sit in the rocker arms, then install the rocker shafts. When the shafts are on pull the coat hanger out. I've had them sit on the side of the lifter cone also.
Good tip I'll try to remember it for next time .