Ford F-350 6.7 V8 Diesel 4WD SRW CC, LB and Towing Capacity

For SRW pickups its almost always the GVWR that's the limiting factor, GVWR - actual truck weight w/ fuel, travel stuff & passengers = max pin weight
The max towing capacity and max cargo capacity are just fluffed up marketing numbers. all the mfg play the same game, not just Ford.
Nothing you do will change the official ratings, but adding air bags, upgrading the load rating of tires and switching to an air pin box are all things that help increase your comfort level. But step 1 is find a slightly smaller/lighter 5'er