360 /380 hp crate engine noisy valve train
You might check!
I have a couple of magnum engine books not by Mopar, which I can't find at the moment, and one of them states that some Magnum rocker bolt holes aren't drilled and tapped deep enough in the heads. He suggests going back with Grade 8 shorter cap screws and washers.
Ace is the place.
Hope this helps prevent some real problems.