I just asked the same question as " 74 power steering".
I have some play in my box, but I called several knowledgeable guys in the Midwest and they're telling me to try all the other options first. I replaced all bushings with high dollar poly bushings and it helped lots. I also replaced center link, drag link, stabilizer, etc. and these also helped. I was told there is a particular way to set up the steering and that my '74 had a center or sweet spot in the steering. I posted the question, but I've gotten no responses yet. I called a seemingly knowledgeable guy in Tulsa, OK. at Youngs offroad. He said they can rebuild boxes, but they're a bitch to do.
The number is 918-437-9393.
Good Luck!
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