hi there,

my first guess would be like this:

image4b.JPG

The plastic unit has to be fixed with screws at the frontend as before.
You should use some grease as lubricant and to hold the balls in place when you put everything together.

Then each steelball probably holds the glass-stick from a different side. One from the left, one from the right and one from behind or from under the flat spring.

I just checked on my Meersburg Automatic 6-3D, which looks like having the same plastic unit.
The 3 balls are centered AROUND the shaft, in a triangle formation 120 degrees spaced from each other, as a ball-bearing !
So one should be in the "deep" end of the plastic V, and the other 2 each at 120 degrees.

Paul