I have a standard saginaw PS pump and notice that my steering is more like power assist than full power. I have a toyota 4x4 power steering box in my truck (upgraded from 1950's era manual steering) that was part of a kit I chose because it kept the steering gear in stock location vs. front frame rail ala GM

A friend suggested an overdrive (smaller) pulley for my power steering but no one seems to offer one for a saginaw PS pump (keyed .625 shaft)

Anyone here have any advice or opinions to share or know of an undersized pulley for a GM application?