Measuring for pushrods.....how many cylinders do you check to get it right?

The subject of preload gets some debate too. I never even considered the amount of it given that most of my builds have been with the stock rocker arms and hydraulic lifters.
Rich was told that the Magnum series calls for .090 preload. My experience with stud mounted rocker arms is just with Chevrolets where it was advised to tighten to zero lash, then some amount of turns beyond that, often between half to one turn.
Today we found that with the rocker arms he has, Rich's setup takes 1 3/8 turns of the adjuster to reach .060. This was merely a test to see what results that a turn of the adjuster gives. This will make adjustments simpler than to put a dang dial indicator on every lifter.