There are many companies that install hitches. Some will even custom fabricate a hitch. U-Haul, Ratco, and 6Robblees are chains in my area.
They will also install the wiring and a brake controller.
Weight guidelines are easy. Somewhere in your coach is a label that gives the GCWR. The weight you can tow is the GCWR (Gross Combined Weight Rating) minus the actual weight of the coach, loaded and ready to go, with all passengers. Yes, you need to load it and get it weighed.
Thus, if your coach has a GCWR of 26,000 lbs, and the actual weight is 21,000 lbs, your towed vehicle can weigh no more than 5000 lbs, IF your receiver is rated at 5000 lbs or more.
Manuals may be available from Ford or Haynes for the E350 cab & chassis. Manuals for the appliances can often be ordered from the appliance manufacturer.
You will be extremely lucky to find any house manuals from Newmar. In fact, if you do find one, it will probably be useless. Those manuals are usually not model specific, they will more than likely cover every Class C coach Newmar built in 1984. You would probably be better off to get an RV handbook of some kind that describes motorhomes in general terms. there have been a few described on these forums.
Once you have the hitch receiver installed, and the trailer wiring taken care of, will you need a braking device on your towed motor vehicle? Yes, it is a VERY good idea! However, it is likely it is not required by law in your state (or many other states, for that matter). BUT, most states (and the Federal Motor Vehicle Safety Standards) have braking performance laws. You must be able to stop a combination of vehicles within a certain number of feet (often 40 or 45 feet) from 20 MPH on a level, clean, dry, hard, surface. If you can meet that standard, an auxiliary braking device is not required. If you can't, said device IS required.
My personal choice would be the ReadyBrute integrated towbar/braking system from NSA.
Some vehicles can not be towed with all wheels on the ground. If your prospective towed (toad) is front wheel drive, you can tow it on a dolly. IMO, the American Car Dolly is second best, but relatively inexpensive. The best, IMO, is the DEMCO Kar Kaddy.
Dollies can be had with hydraulic surge or electric brakes.
Have fun getting set up.
CM1, USN (RET)
2017 Jayco TT
Daily Driver: '14 Subaru Outback
1998 Dodge QC LWB, Cummins, 5 speed, 4X2
2 Kawasaki Brute Force 750 ATVs.
Pride Raptor 3 wheeled off-road capable mobility scooter
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