[Prowbar]

I adjust them with the engine off. I put the no. 1 cyl on powerstroke at TDC, adjust the valves, then do 6-5-4-3-2 and recheck 1. I use a 15/16" socket to turn the engine at the crank pulley. Now this is quite a chore with the big 478, haha. The intake valve closing is something I track on each cylinder.This way I always adjust valves when they are on the base circle of the camshaft.

The deluxe heater on these trucks with the V6 is a big obstruction to work around. Kind of wished mine had the simple heater to make engine work easier.

I love the self locking screws these engines have. Also it doesn't really matter if you adjust the valves hot or cold, the literature mentions the aluminum rocker arm brackets compensating for the valve lash based on the expansion difference on aluminum vs steel. I've checked it a couple of times and it is almost always spot on.

As for the .030" play in the rockers, yep that is a typical thing.