Rocker arms for 408 build

So I went to the shop and pulled a rocker from a stock Magnum head. Amazing how having it in your hand gives clarity. Should have done it before... (duh)
It's obvious how much stronger the pedestal is than a stud. That square pedestal sits snug inside the guideplate channel (edited). My bet is its more stable than a 3/8 stud with girdle.

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