Upper control arm bushing extra part?

I know there are a million posts about how to replace uca bushings and I watched video's and read forums but was surprised to see this extra spacer (?) on one side of the uca but not the other. It was hell to get the bushing out and I ended up cracking this "extra" part. The part in the pic shows the cracked ring that was on just one side of the control, not the other.
Can I just install my new bushing without that part?