[ohcbird]

It's either a Metripack, or Weatherpack...but the info below applies to both styles.

If you need a part #, then have a GM guy look up the vehicle end of the connector (the one not on the hub), then just get the cavity plugs. They are designed to seal up the slots where a wire is not used. If they have a Metripack bin, you might be able to find everything in there. The plugs themselves are cheap.

If that doesn't work, You can get the Metripack connector & use the cavity plugs from an electronics supply house. To find the plug it mates to, lookup the part # on the connector itself. most good online search catalogs also list the connector that it is designed to mate to. Try Mouser electronics, or Digikey; they both carry the full line of Delco connectors.