350 5.7L , I recently changed one head, I used the same push rods and rockers. When I tightened down the nuts on the studs I reached zero lash before the stud cleared the top of the nut. Normally there’s about 1/4 inch of thread sticking out the top of the nut. What am I missing or what could be the cause? Stud height is the same on old head and new head, the only thing I’m thinking is the Spring tension on the valve. The lifters are sitting in the correct spot