最後に、検索に引っかかるように海外のコメントを。
These problems on the steering rack are common on the F series, u can feel it when u drive it over a pothole or when u shake the steering wheel with the engine off.
in the video u will find how i managed the situation and the result of the work. i don't recommend changing yourself, but if u feel so, be free to do it on your own risk. There is a procedure made by BMW of installing this kit that I did not follow. But i saved 300$ and that's make me happy.