Jim,
First off, what type of rack do you have now?
Second it can be done. "MARCH" pulleys has finally made a set of pulleys for either a left or right hand turn water pump. Simply buy a set of pulleys and brackets from MARCH. Then find a new or used pump, two power steering hoses, and a rebuilt power steering rack. NAPA has them at a fairly decent price.
Then after a few hours of labor installing all the parts it will simply need to be re-aligned.
Cost: Conserveatively $850.00
However if you are using a power rack that has been "blocked off" then may I suggest a Flaming River rack. Around $200.00 and you will think you have power steering. If you have a FR rack then see above!
DV