NIC's show up automatically in the Failover Cluster Manager. Mine were not showing up because I had two Heartbeat connections configured on the same subnet. All I had to do was remove (or change) the IP on one and there it was. The Failover Cluster realized
that they were on the same subnet and only added one. Hope that helps somebody else, it was driving me crazy.
Marked as answer byjob12354678Tuesday, April 23, 2013 8:33 PM