WOW...now that's a move. All I can advise is on the transport. Possibly you can "Chicken Proof" the backend of the SUV, I assume you mean something like a Suburban, by covering everything with tarps, and build a chicken Kennel that is as tall as the inside roof and as wide/long as will fit the space you allocate. Giving it some height will allow for a roost bar and maybe a small nest box, which could be a cardboard box with a hole cut in it. If you don't want to tarp the entire backend of the SUV, you can make a "wrap" for the kennel out of cloth or tarp, leaving the top uncovered for light and air. To allow the hens some time out of the kennel you can get an exercise pen that is made for dogs, use your kennel wrap for a top while the hens are in it. Exercise pens fold up so that they are only a few inches thick, have no bottom and no top, but would allow you to have a place to let the hens get into some grass (if you can find any) and allow you to clean the kennel out. If you make a kennel wrap out of fabric you could use velcro to keep it around the kennel. I would put an extra opposite velcro on each end so you could stretch it over the top of the exercise pen and velcro it on. Or in leiu of needing a top, you could clip the girls' wings....personally I don't like the idea of clipping their wings, but if them flying out of anywhere during the move is a possibility, then it might be something to consider.
You may also want to get them used to the travel kennel prior to the move......Wow, you are very brave, best wishes with the move, I hope all goes safe and well.
