When it was in the sink I noticed the parts washer solvent passed right through the middle of the shaft where oil is supposed to flow. I was like, "that ain't right." Turns out there are supposed to be cork plugs in the ends of the hollow shaft to contain lubricating oil so that it flows to the rockers and out the hole in the top of the rockers to the pushrod and valve stem. One plug was gone and the other was degraded enough that there was a 1/8" gap. There is no way anything was getting much oil as it simply ran out the end of the shaft!
I replaced the plugs with plastic ones, and pierced them with a pick so the cotter pins go through them.
Just thought this would be helpful for anyone who has rocker noise that just won't go away. If you run the engine at low speed with the valve cover off, you should be able to see oil flowing out the tops of the rocker arms and not dribbling out the rocker shaft.
My father told me to set valve lash at .014" intake and .018" exhaust, is that about right?