If your having problems with the steering at speed please tell us what it is beside "numbness" in the steering wheel
Have you had or drove any other Mopar brand car built after 1956 that had the Mopar type and brand full power steering ?
If not they are a lot different steering, way easier, than the power assist like Ford and GM uses
Have you thought about having the steering box rebuilt and maybe have the ratio changed so it is quicker turning, that usually provides a little harder turning, especially at very slow speeds, which some people like
My first Mopar was a 1959 Dodge Coronet with Mopar power steering I bought to go to work in 1964, it was really easy to over steer in traffic in SO CA even back then
I now swap out the power steering for stock manual steering to make them drive better and loose a bunch of weight on my race or and street and hot street cars, around 60 Lbs. I think, off of the front end
Good luck on your deal