Good looking work! Since the original rocker arms don't have bushings, I wonder when yours were modified? There's another approach, one I've been working on for a while. Grind the rocker shafts down to 18MM diameter, and fit Torrington roller bearings to the rocker arms. I use a tool post grinder on my lathe to rework the rockers, and fabricate bushings for the rocker stands to accommodate the smaller diameter shafts. I have a fixture that fits my valve grinding machine to resurface the rocker tips.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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