that sounds more like something is loose. Like maybe the steering box is loose. Maybe the attaching bolts are loose, or maybe the k-frame steering box mounting bracket is cracked, or broken. You say everything was replaced by PO? are you positive? could some of the parts be defective?
Have someone crank the stg wheel back and forth(while tires on ground), while you crawl around looking for slop in the steering linkage.
