1) You need 7/16" studs for the roller rockers, as the factory 7/16" positive stop rocker studs will not work with the aftermarket rockers.

2) You need hardened pushrods to go with your guideplates. Further, depending on which brand rockers you have, the length of the pushrods needed will vary, in order to acheive proper rocker arm geometry.

3) The rocker lash should be adjusted while the cam lobe for that rocker is on it's base circle. The less preload, the better...I usually go just a 1/4-turn past zero lash, but you may need more.

Paul