With a stock (7.794) pushrod the bottom of rocker-ball looks really close to the hex-head on the stud. About .060 when closed. The witness mark on the valve tip indicates that the geometry is pretty good with it being just inboard of center, but it just seems that the rocker-ball is too close to the hex head. I tried a .100 longer push rod and it looks a lot better, and only moved the witness mark to just ouboard of center. A .050 longer pushrod may put the mark in the center and bring the rocker-ball up 1/2 the distance. Is there a minimum rocker-ball to stud hex-head distance. Thanks
Any possibility you're bottoming out a hydraulic lifter to do the test? At that clearance a half turn of the nut would make all the difference in the world.
Hard to tell from the pic but it looks like you could mill a little more off of the stud boss on the cylinder head. Rocker almost touching stud hex and it looks like you have a ton of threads above the adjusting nut. Take about .125 off and the problem will be solved >>>>.
I like to use a soild lifter for mock up but it looks like you've passed that stage as you already have the intake on. Surely you can feel the preload take effect on the lifter to stop cranking the nut down before the plunger bottoms out. Still looks like too much material left on the stud boss >>>>.