Hi, apologies for the long winded post. I have just fitted the an old Isky 505 solid cam shaft, lifters and adjustable rockers from my 383 to my 440 (changed push-rods for 440 ones) the problem I have is that when I adjust the rockers on to the push-rods, I do not have enough thread left to fit the lock nuts. I have fitted the lock-nuts to the underside of the rocker arms and although the surface is rough cast, nuts are making contact all the way around. I work for a Cat dealer and have checked with the mechanics there and they all see no reason why I can't do this. My questions are will this be OK or should I try and find longer push-rods (not much available in Aus) also what are the valve lash clearances? Any advice would be much appreciated.