My F450 is a 2010, but it is a Lariat. I'm not sure what removable tailgate means, but my tailgate with step is very heavy compared to one with out. If I remember right it weighs about 100 lbs compared to a nonstop that is about 60 lbs. It also has a camera builtin. It's fairly hard to remove/install due to the weight, but still removable. It would be hard for me to believe that the Ford will build a tailgate that can't be removed, but who knows. I'd ask the dealer about that feature.
As far as F450 pickup vs F550 chassis goes, we wanted a truck that looked more conventional at the time without a flatbed. The spring pack and frame are quite a lot different between the chassis cab and pickup with the chassis cabs having a straight frame. All of the chassis cabs have more capacity the last time I looked. You may find that even the F350 Chassis has as much capacity as a F450 pickup.
We have a 9 1/2 ft heavy camper. If you go larger, maybe you really need a F450 chassis or F550 chassis.
'10 Ford F-450, 6.4, 4.30, 4x4, 14,500 GVWR, '06 Host Rainer 950 DS, Torklift Talon tiedowns, Glow Steps, and Fastguns. Bilstein 4600s, Firestone Bags, Toyo M655 Gs, Curt front hitch, Energy Suspension bump stops.
NRA Life Member, CCA Life Member