You need dual rear wheels for that setup to be able handle the pin weight on the rear of your truck or will need to upgrade to 19.5" wheels and some suspension aids. I'm not sure what specifications changed for your year truck, but mine is rated for 14,400 lbs fifth wheel towing with 6100 lb rear suspension over a 9750 lb rated axle. Your power train may not be able to handle the weight without regearing your axles.
Your choice, if you decide to purchase this TH, is to spend significant money to upgrade your current truck or buy a larger one.