PS conversion concept??

I've been reading all these random acceptable and non-acceptable donor vehicles but I don't really understand the concept of why which ones will work and which ones won't. I understand the pitman arm and steering shaft need to match my '72 because the splines are clocked differently, but how about the pump and box? What is different between them from a 6cyl to v8?

 

The mounts are different between the V-8 and I-6 so don't interchange. Pulley offsets can be different as well.

What BKD said about the box. Also, metric fittings vs. compression fittings can come into play as well.

 

Would it be safe to say that any jeep and more specifically any CJ with a V8 would be a good donor?

 

If you have an AMC V-8 then yes. Be aware that '76 and newer steering box mounts were angled different than '72-'75 so the "clocking" on the pitman shaft is different so the angle of the pitman arm will be different.

 

Could that be fixed by either fabbing a new mount or getting a pre-76 one?

 

I just re-read your original post and see you have a '72. You just need the pitman arm to match your '72. Thinking back I now remember it's the pitman arm that's clocked different not the steering box. Momentary brain fart on my part, sorry for any confusion there.
You could use a '76 and newer box with the '72-'75 power steering pitman arm and should be good. The manual steering pitman arm has a smaller diameter hole and splines where it mounts to the pitman shaft so won't work.

 

Here it is:

http://www.4wd.com/productdetails.aspx?partID=12471

 

I used a 92 xj box on my 72 with the pitman arm mentioned above. The stock 72 manual steering shaft splines fit the 92 box and I don't find it too twitchy to drive.