I'm curious what that Fuller transmission weighs too. It might be heavy.
Since there are guys out there putting the Cummins 6BT into trucks with that suspension and it weighs even more than your V-6 I don't think you'll have any trouble with the stuff working. You might need to address the spring rate as KC in NH said.
For my Cadillac 500 powered tow rig I'm using that same suspension and chose one from a big block powered C20 in part because I believed it would have stiffer springs.
Your motor choice interests me. Can you explain how you came to choose that motor? Its not known for its power output, economy or revs.
1-ton or 1-1/4 ton? Are you starting with a truck that is one of those? Or planning to build based on one or the other? If going with 19-inch 5/10-lug wheels the 1-1/4 seems more natural to me. However it may mean more work to get the front suspension and brakes setup.
What frame are you using?
Please keep posting about this truck as you conceive and build it. I'll be very interested in following along.
