Dean: Given how much that type can be adjusted as compared to the eccentric Gold Star setup there has to be something really amiss in the valve train.
However when I look at the amount of threads on the cam follower and how short the engagement peg is on the pushrod I would think that you could shave a little off the locking nut (on far right in second photo) so that the engaging nut could be threaded little further down onto the cam follower stem. A few thou would be easy to attain.
The only snag would be that the rocker geometry could be seriously incorrect. If you are using the standard 2420 cams then the geometry change might not matter given the limited lift they provide.
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