First off, when tying a vehicle down to a trailer you should always attach to the frame, criss crossing the straps, and make sure to put a load on the suspension. If you just tie into the axel you will have 4k of weight (the body) bouncing along to its own tune - not good.
Second, have you considered flat towing? Several years ago when I got my M715 I had to go to the middle of Spice's state (Pennsylvania) and the numb skull I was going to borrow a trailer from broke the axel the day before. To add insult to injury I cut a tire on my big truck as I pulled it out from the barn (you can insert as many explatives here as your imagination allows). At any rate I flat towed my '15 thru three states with a ty '85 chebby 1/2 ton with no more damage than the wonderfully engineered chebby 10 bolt coughing up an axel a week later. Once you get used to the increased breaking distance it was no problem. While I wouldn't recommend extended duty around town you'll be on the interstate almost the entire way, right? Pull the drive shafts at the pumpkins and zip tie them out of the way, make sure the tow bar is securely bolted on and go. Don't tie down the steering, it will follow you right along unless you already have a REALLY bad alignment. For a couple of hundred you could buy the tow bar and some of those wireless magnetic base brake lights to put on the back.
If you do want to b. out (I mean wuss) check out this web site: http://www.movecars.com/toc/find/index.htm#by_state
I used it to get my '71 Blazer from Western Montana to Michigan for just under $700.
Good luck, and drive safe.

Ron