[T2] Insulating ring

[c.dreike]

Hi Guys,
There is an item called "Insulating Ring" inside the steering tube below 
the steering wheel.
In the Bay Bentley manual, Steering section 2Â  page 27 diagram the item 
11 is shown around the middle of the tube.
In the 68 parts manual it is called out on page 4-12 as item 12 part 
number 211 499 599A.

My 71 bus is missing this part. I'm not sure where it fits in the tube, 
and I'm not sure of its function.
It is NLA however I could cut something similar from some sheet 
polyethylene and tuck it in.

Can anyone tell me exactly where this piece fits in? And maybe what it 
really does?
I have the whole steering mechanism out of the bus presently. Cleaning 
and painting all the parts.

Thanks,
Chris