Rear Axle Setup...what goes where (2002 EC250)

[lynngarner]

2002 EC250. When I removed the rear axle yesterday, the pictured washer fell off the axle on the left side of the hub. Here's the order of what I found (left to right) on that left side of the hub: axle end, adjuster, swing arm, the funny washer pictured here, metal seal cover, seal,and bearing. When I went to re-install the axle, I could not find a home for this strange washer. It is flat on one side and has a raised portion around the inside hole on the other side. This raised portion is cut away equally on two sides of the raised portion. It seems that the raised portion should fit into the slot of the axle adjustment, but it will not go.
Please help figure out where this goes on the axle, what the raised portion goes into, or whether the washer actually belongs there at all. Thanks.
Lynn Garner