Further feedback on this conversion: I did it on my 1992 Explorer last weekend. I did have to replace the pressure side power steering hose as my original leaked immediately but it was pretty crusty so I'm not sad about that. I got a junkyard pump, reservoir and pulley for $50 so I had about $120 into the conversion. My old pump was making a chattering noise when it warmed up so I am sure it was on its way out.
My initial thoughts are that the conversion was easy and cheap. It is definitely very quiet and required almost no effort to bleed the system. The bracket kit is well made and the instructions are easy to follow.
A secondary issue I had was my power steering would not function at all for about 30 seconds at idle on a cold startup (with the old pump.) I was pretty convinced that it was the pump at fault but I am pretty sure I still have this issue, it's just not as bad, seems to happen for maybe a couple seconds now at most. If I rev up the engine a bit it'll start working. Not sure if I still have air in the system, kinda doubt it after 200 miles but it's possible I guess. Maybe a fault of the steering box, I replaced that with a reman unit a couple years ago. I am going to continue driving it as-is and see if it works itself out... I may try a different size pulley as well... it would be nice to have more fluid moving at low RPMs. None of this issue is a fault of the Jeep pump or Proquipped kit, I think it's just a quirk of my truck in particular.