You can make most any PS conversion work with the original steering column.
Some of the vendors sell a steering column lower bearing and adapter bushing to use when you cut the shaft and jacket off the old box.
Then you can use Borgeson or Flaming River joints and shaft, or scrounge stuff from the junk yard.
http://www.borgeson.com/http://www.flamingriver.com/That is what I did for my truck, I used Borgeson, but will probably use Flaming River in the future. I have also used u-joints and shafts from the junk yard in another truck, that way is by far the cheapest if you can find what you need.
Grigg