[Jabes1]

You don't have to hack up a valve cover to set the valves on a running engine. At idle its not going to spray everywhere, the worst that's going to happen is that it will DRIP onto your wires and exhaust manifolds/headers and smoke. Everybody has a different way of setting lash, I set the lash on a new cam during break in a little on the loose side, then do a running lash, but that's just me. Some people set lash one full turn on a running lash, I only do a half turn on a running lash... once again just me. Its hard to screw up, unless you really crank down on it. I believe using feeler gauges and dial indicators is more precise, I used to set up my turbo diesels in the military that way. I'm just too lazy to do it on my SBC.