Remove rocker studs. Order 3/8" guideplates. Put 5/16" plates on craigslist. Measure total length of stud, then measure from bottom of hex nut to top of stud. Call Crane, give them the measurements and cam specs and order rockers to match. Being a race motor, you may want to change the whole shebang over to 7/16", so I'd wait to talk to Crane before ordering guideplates. Badda Bing, Badda Boom.

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