I looked at that part number on Summit's site. I don't know how Ford/Chevy/AMC could be covered by one rocker. Chevy rockers are known for being too short from pivot to tip for AMC use. Ford applications are much closer, but sometimes the slot is too short and the rocker hits the stud when the valve opens. I'm running Crane Gold rockers (35750, I think) on both of my 390s, using 70 heads (291C) and .100" longer than stock pushrods. Harland-Sharp are very good, I believe MC sells the Scorpion rockers right here at the Bulltear store.
Bob
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