Well, if you're looking for a little road trip (I look for every road trip chance I can find since buying the KJ CRD
), I'd say do it! Sounds like a fun trip. I like the 2X4 box spring idea. Wrap it well in tarps and put it on the KJ. Put the Focus on the dolly, then wrap the mattress in tarps and lash it to the Focus. It'll cover almost the whole thing, but who cares. Wrap it well in tarps (or a cheap car cover) and lash it to the Focus with a bunch of nylon rope like a spider's web. It'll form fit over the car and you won't increase you're C.D. much more than the Focus alone would.
The box spring's going to eat your fuel mileages, but who cares...he's paying for it.
Make sure you get good working tail, brake and turn lights to put on the back of the rig!
Great advice from everyone about your towing strategies. Also good ideas on just donating the set and buying new at the destination...if you're not looking for a trip.
But, personally; Pay for food and fuel, give me a road map, and give me the time off work and I'll haul ya to Pluto. Just a good reason for a road trip and more stories to tell around the campfire.
Good luck and keep us posted. Take some picts, I wanna see that rig after you get it all lashed down!!! That'll be GREAT!