Before you adjust the hood, check the alignment of the cab. There are specs in the Truck Shop Manual for the correct gaps between the bottom of the cab and the frame at the front and at the rear. Having these gaps out of whack will alter the amount of shims needed under the radiator support.
As far as the hood adjustment, all that you are looking for is a tight fit on the hood seal, a 1/8 to 1/4" gap at the back of the hood, and that gap needs to be parallel to the cowl.
After you accomplish that, then you can put the lower hood latch on to determine how much shimming needs to go under the radiator support.
You will know that you have it right when the hood latch is in the closed position and the hood lines are still parallel at the cowl.
Carl
