I was looking at them this week...If you are pushing the axle forward 4-8" it'll bolt to the saginaw mount in a CJ...but....
The high pressure hose is an O ring at the steering box, and likely flare at your power steering pump...so you'll need a custom hose. You'll need a joint at the steering box and cut your old shaft and sleeve it with some 1" DOM to fit it to the astro box. Those joints are not cheap ($80) for the scout one I bought.
I went with a scout box outside the frame, and if you can weld and stand drilling 3 BIG holes in your frame, it's a better choice IMO. It gives you a short steering shaft to the column, and you can use your factory power steering lines. You can mount it where you want to deal with anywhere from 2" stretch to 12" stretch.