I'm putting my 462 together for my boat, it's nothing crazy, stock Gen VI block, hydraulic roller, profiler 290cc heads. Using a .250 long intake valve, .100 long exhaust valve, stud mount Comp Ultra Magnum rockers #1620. At full lift my rollers are over halfway off the stem of the valve. I can use a slightly shorter pushrod and it's not as bad, but if I do that, the rockers hit the polylocks. Is there a slightly shorter tip rocker I can use without going to backset crowers at $600 a set?