PN inquiry: Round fastener for large connector near battery terminal in engine bay

[CaifanSC]

I recently changed the alternator wire on CD0144 and when putting everything back together I noticed the large connector near the positive battery terminal and near the heater valves was a bit wobbly. Apparently I'm missing a round fastener/wheel/ring that holds the male side of the connector (that goes into the firewall) in place when in the bracket. I've searched the parts catalog and I can't find a part number for it. I was wondering if anyone has it handy.

I borrowed an image from the web and I circled the connector in yellow in the picture attached. Any help identifying the PN is greatly appreciated.

Thanks!