The adjuster ring is part of the axle assembly.
It should all come out with the axle.

The lock is on the passenger side.

It is a hook shaped piece of stamped steel that gets locked under the second bolt down from the top towards the front in this picture.
It fits in the notch on the threaded ring and holds it all in place...



Notice the nut holding the lock is the only one with a washer on it.
It should go back together this way.

Hope this helps.
also Art.