The rubber rings are support rings to hold the far end of the axle close enough to center to find the carrier. Without them you will have to lift the far end off the bottom of the axle tube by forcing the close end (in your hand) downward. Doable. But running the support will make it easier.
You should be able to press that axle out of your bearing unit - support the hub flange on the press plate and apply pressure to the axle end. dont hammer it or it will swell and lock even tighter.
J Wm Bishop EA, ASADE
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