I believe too there shouldn't be a problem running at max pressure. One guy brought his rig for a new set of xd wheels and radial tires and he prefers at max pressure. See if it will ride a little rough for you.
Stumbled on this thread and nice to see that cool truck! That's is a sweet find. Reminds me of the project truck of my buddy's uncle. 1992 F150 2x4 6" suspension lift, Motometal forged wheels, and 33" tires.