I am replacing the Shifter Arm Seal on my Fordomatic. I have it apart on the Bench ( out of Car). Ready to re-assemble. The Ford Shop Manual suggests using a piece of Tubing to compress the Detent Ball and Spring.  Has anyone else found anything else that works better? Haven't tried it yet but the Ball disappears quickly if not compressed and held. Ask Me how I know. See the attached Picture from Shop Manual.