there are lots of choices for powersteering conversion these days. first of all there are two main choices do you want to stick with stock or go aftermarket. chockostang sells a kit to basically put the stock style powersteering on your car. aftermarket there are again two main choices either the borgeson powersteering gear conversion which looks pretty straight forward or rack and pinion steering conversion. a lot of this decision will be like do you like red or blue paint. everybody has there own opinions. when I build my first mustang there was only one aftermarket option and that was total control rack and pinion which I still think is the best system out there, but that is just my opinion. I have done 2 of these and I am very happy with the results. I have been driving my first one since 97 with no problems. but there are several rack and pinion conversions out there.
if you do a search on rack and pinion you will get basically most people will tell you the best is whatever they happen to have on there car lol. but maybe you can at least see which is the most popular. I suspect what you are going to find is that the most popular will be what is cheapest not necessarily best.
anyway good luck.
65 mustang. supercharged 302 currie 9 inch, 5 speed.
67 mustang built for my daughter
89 convertible lx in progress
click on the house icon to see my garage page with build info.