I changed from manual to power and there is a huge advantage to power. The 16:1 ratio allows for much quicker manuevers in emergency situations. This swap completely change the character of my 68 Barracuda, it went from feeling like I was driving a barrage to feeling like I was driving a nimble sports car. I drive my car daily in the summer months and dealing with 16:1 manual steering during low speed manuvering is just not acceptable.
Most of the over assisted feel of mopar power steering from the 60's and early 70's can be adjusted out by cranking in more caster than the orignal factory specs and by using 60's series tires up front. If the feel is still to over assisted for your taste a rebuilt box from Firm Feel or Steer & Gear will give you the same feel as a modern car.
