Cam choice?..

I know my Duster has 354's with 27 3/4 in. tires and I'm at 3k at 65 mph...

But that is the sweet spot for your Duster.
Your truck will be rapped out at 65 with too small of cam.
I am not suggesting a drag cam ... just one that gives you a usable mid range.
I find with today fast hiway speeds even 3.55s seem too deep without an O.D. I never thought I would find myself saying that .