What would be the minimum clearance between edge of valve spring retainer and the bottom side of rocker arm on a oem 426 hemi rocker ? Mine are touching in the closed position. Thinking of clearancing the rocker arms with a rotary file, but i dont know how much meat i can safely remove without compromising the strength of the arms. The arms are stock narrow pads that have been resurfaced by a well known builder. would .050 be enough ??