I didn’t like the suggested method in the manual how to connect the tube coming from the control column to the bell crank. The manual suggested to leave off the jam nut. That would mean all the movement in the tube (originating from moving the control column forth and back) had to be covered by the screw thread inside the tube.
I changed this as suggested by the fellow builders on the Murphy Builders List: I installed small pieces of 5/16 tubing (1/4 ID) at the bolt. This way the movement can be covered by the bearing at the rod end. A jam nut can be installed.