I have hydrolic lifters in this engine. I guess you are talking about putting the camshaft on the back side of the lobe, and then adjusting the rocker arms, and if so, what size feeler gauge should I use? Do I do it when the engine is cold, hot or what? I've always thougt I was a pretty smart fellow on these old motors, I grew up working on them. but either I forgot how to set the valves or I'm not as smart as I thought I was. Sorry, I'm 50 years old, and I may be losing my mind.