I looked at the inner bushings of the sway bar, with a jack under the bar to use the car weight to push up on the bar, and there was a definite gap between the bar and bushing. I put some aluminum shims in, about .025 thick, bent approximately right with needle nose pliers, and this noise is gone. Then went to my other American car with a worse knock noise, same probelm, bigger gap, used .125 piece of aluminum. No noise.
I had replaced the steering rack in the 850 on someones advice locally, they thought it was the inner tie rod ends causing noise.