Steering box washers

[Russell Reay]

In disassembling my steering box I took photos of every part as I went--good thing! The end plate did not have an anti-leak tube, and right behind the light switch bracket were a concave steel washer and a thick cork washer / spacer.
Reassembling the box, and using an end plate with tube, Les' sketch does not show the washer or cork piece. What are their function? I would attach a photo if the website would allow.