I just did a power steering conversion about six months ago. I called a few wrecking yards and they sent me all the parts I needed. Gear box, pump, belt, resivor, pump bracket, stearing shaft, pitman arm, and hoses. I think that is all ya need. It was a really easy conversion and would recomend it, over the manual steering box. My box was going out so I decided to put power steering on. I did not notice any power loss.
I have 35" tires and I can now turn them on dry pavement without moving.