Max Fifth Wheel Advice

[mdshope]

Need some help. The more I dig into this the more lost I become. Salesmen at dealers seem to be all over the place as well. I am trying to find out what is the heaviest fifth wheel and pin weight I can handle. I have a 2012 F250 crew cab 4X4 King Ranch with the 6.7L turbo diesel and 3.55 rear axel. I printed the 2012 towing guidlines for Ford and what I found is the GVW is 10,000 and the rear axel has a RGAW of 6,100 the overall GCVW is 23,500 and it has a max fifth wheel tow weight of 15,200. I wish it was as easy as saying my loaded fifth wheel has to be under 15,200 but it isn't. My wife and I are looking at a Keystone Montana 3811MS with the legacy package and several of the Forest River Cardinals. Any direction on king pin weight and loaded fifth wheel weight for my vehicle would be great. Also curious to see what other similar trucks are towing.