What TV would I need

Hi - planning out the retirement present to DW and myself. Going to the Eagle Cap website they have a handy "build your own" interactive page that allows you to list the camper and any options you want. When complete they give you a wet weight total that includes water, propane, etc. along with the weight of the added options. For the 1165 model the wet weight is 5600. I figure around another 500 lbs of stuff which brings me to 6100. In addition I want to pull my jeep on a car hauler which is around 7000 so I figure the tongue weight is around 1000 bringing the total payload to around 7100 lbs.

I live in CO and mountains must be climbed which leads me to want a diesel. I have been looking at the RAM 3500 dually with Cummins/Aisin. However looking at the Ram towing guide the max payload is around 5600 which leave me minimum 1500 lbs over.

What mods would I have to do to this truck to safely handle this load?

If I wanted to find a diesel pickup that would be rated for this load without mods, what would be my choices? I see the RAM 4500 cab/chassis but don't what is involved in going this route.

When I started looking at this I naively thought that a 1 ton diesel dually would be able to handle any TC I wanted to load on it but now I'm getting worried that that may not be the case and I will either have to go to bigger TV (more $$) or scale back on my TC because of weight.

Thanks...