A lot of the time, the Chassis Model Year is the year prior to the Coach Model Year. In your case it seems your 1984 coach is on a 1984 Ford Chassis.
We had a 1984 Coach (24-ft Holiday Rambler Ambassador) on a 1983 E350. One difference I'm painfully aware of, is that with a 1984 Chassis, you can use late model 16-inch wheels to easily replace the 16.5's that 1984 used. 1983 had an earlier design wheel that was difficult to replace. So Good on You.
C6 three-speed automatic transmission has the well-earned title "Bulletproof."
460 is The Beast of V8 Gas Engines. Takes a Diesel to outdo one at Towing.
You can expect Exhaust Manifold problems. Leaks, broken bolts, maybe cracked manifolds.
Brakes are marginal. Equip your Toad or Trailer with Brakes.
Chassis drives better then the current one.
You'll be at, if not over, GVWR loaded for a trip. They didn't talk GCWR back in those days. I'd peg max towing at 3500. Stay under 3000 if you can.
Shop for a Hitch where you can do measurements. Ford came out with chassis modification (stretching) standards, but not way back then. We had a welded-on hitch. Bolting is better. You might be able to get a lighting harness that simply plugs in.
I did a number of low cost mods or repairs that improved its ride, handling, and performance.