[Prowbar]

My engine oiled very little to the heads before I milled out the slots in the camshaft to increase the oiling. Now I get a lot more oil to the top end - can't hurt in my opinion.

I set the valves with the engine off. I remove the valve covers and put a wrench on the front crankshaft bolt and start on cylinder 1 at TDC at the compression stroke. I set the valves following the firing order, making sure I am on the base circle of the cam.

Ignition timing is usually set between 8-10 degrees initial. I check dwell with the dwell meter (I have a distributor without a window) I take off the cap and remove the rotor. Then slightly loosen to the hold down screw of the points and use the screw driver slot to adjust. Takes a couple of times to go back and forth since you need to put the rotor and cap back on and run the engine to check the dwell.

The nice thing about the GMC V6 is that you can set the lash with one wrench (no hold down nut to mess with) and that the rocker pedestals are made of aluminum, thereby keeping the lash the same between hot and cold due to the larger expansion/contraction rate of the material. I have read in the advertisements that you can set the lash either hot or cold and that the lash is always the same - and they are correct! No need to add any lash when cold.