Quote Originally Posted by TOW'D View Post
Fresh valve grind on marine 7.4L Mercruiser.


Something is odd here, as it doesn't appear that you have traditional rocker studs holding the guide plates "Hi Performance guide", down to the head.
It also appears that you have bolts holding everything down instead of nuts, which suggests to me that the valvetrain is intended to be non-adjustable, ie: simply tighten the bolts down tight and go, no normal adjustment needed.
It's been a long time since I've been inside a BB Chevy, can't say for sure if or when they switched to this system.
I would talk with whomever did the valve work and see what they say.

Typically you should have something like this, stude with threads on both ends holding the guide plates, rockers slip down over the threaded studs and then a nut adjusts the rocker.