Valve adjustment.......
I have a 74 Dodge Dart slant 6 225. I've read sooo much ay setting at normal operating temperature. This is what I did. My adjusters didn't want to turn. So I measured the temps at normal operating temps. 1 at a time. 170 degrees was too cold, 180-185 was the trick. Set 1, ran for a few minutes until the next came up to temp, then set. This worked out absolutely awesome !!! The valves were so noisy, not now. Found I had a fuel pump arm slapping, that's next. 1 thing at a time folks :}.
I worked in a brewery for 25 years and that's we would set the seamers for cans of beer.
Hope this helps with " normal operating temps".