OP, you have absolutely nothing to worry about. That is a very lightweight camper for your super duty, period. The first limiting factors would be tires and wheels, and your even under the original 17s with 3195 lb tires. Newer 18s = even more factor of safety.
Tailgate or not is your call. If you need it, make the mods to keep the tailgate on.
Sometimes I run with the tailgate, currently I have a generator mounted back in the “wing” that doesn’t allow it. I pack a2x8 to fit in the bed slots to make a short tailgate when running bobtail without the camper when we’re on the road with the camper.
You don’t need much clearance between bed rails and camper. It’s not a thing as long as you have a few inches between the roof of the truck and the overhead on the camper.
Have fun camping! Nothing to worry about from a capacity standpoint with your truck.
(But you may prefer to add a sway bar or other suspension mods to stiffen up the rear end.)
