Thanks clarkz71

Interesting ... of the 3 connectors I've had, all have had black 0-rings, not white (the original connector, one replacement from ********, and one replacement from the dealer).

Regarding your comment that the harness plug won't cause a leak - does this mean that the design of the connector is supposed to prevent the fluid from entering the connector? It seems like this should be true, but I've been having a hard time trying to figure out what prevents the fluid from entering the connector through the holes in the bottom of the connector (the holes that the electrical pins go through, and the other holes in that area).

Thanks again clarkz7, and to anyone else who can add anything about this!