Adding power steering to a 63

[Mack B]

So I know this has been beat to death, and I just wanted some more opinions. First, ill be getting my bracket from captain fab. Do most of you get a remanufactored box or one from a junk yard? Just curious if these things typically wear out, my example is the 50 year old box on the truck now is sound just a nightmare to get in and out of my garage (think 12 point turn) second this truck has what I believe to be the original 283, did the 73-87 trucks use short water pumps? Just wanted to see if I could get everything off the same donor if I go that route. In searching I found out about the sae and metric boxes, any advantage or disadvantage of either?
Pic because everyone loves pics