Alright, I have a 5.3 with milled 862 heads at .015 I recently did a cam swap to a Lunati part# 20540720 with new dual springs. I was running stock rocker arms and pushrods and it has slight valve train noise, so I decided to get roller rocker arms from comp cam, the ultra gold non-adjustable 1.72 ratio. I put those on and it's pretty noisy, like knocking noisy. I go to measure pushrod length following vettenut's method and a few other on the forums. I end up with 7.257, I adjust the pushrod length checker for preload, I put the pushrod back in, snug down the bolt and when I spin the motor around the rocker arm loosens up and there is at a little less than 1/2 in gap between the pushrod and rocker. I've done this about 5 times with the same results. Any ideas or thoughts would be appreciated.