In no particular order, and I haven't ever done this, but having seen other threads over the years with the same questions, you would need to verify the strength of the frame extension under the coach part of the RV as well as the entire frame and reinforce as required, upgrade springs/shocks all around, upgrade brakes all around, verify the steering system capacity, verify rim and tire weight bearing capacities, and that's the short list. Suggest you ask the Motorhome manufacturer, if they're still in business. They'll give you the rest of the list, and the caveats, as well.
It would be easier to just buy an RV that can tow your Wrangler four down without any additional modifications.
