Another question on this 454. While adjusting "zero lash" I've read tighen down on the rocker while rotating the push rod until there there is slight resistance and then go about 1/2 a turn more. Not sure if I can discribe this right but if you can push down on the push rod and there is a little spring back do you adjust down until the spring back is gone and then go another 1/2 turn? Should there be any spring back? In other words it seems like when I push down on the push rod it is compressing the lifter.