Power steering help

[Rugman]

I changed out a growling powersteering box on my 1972 C-10 i went with a 1977 used box that seemed in good shape, at the same time i instaled a new pump from NAPA and fit it in to my Reservoir. Now the steering is a little to free. What i mean is its a little to easy to turn? I have a Finished 1971 Short wide. That has perfect feeling steering but it came that way when i bought it. What should i change to get the steering more firm. The box i installed is Quiet and tite and so is the pump. Thanks for any help you can give.