Been there, done that.
Double checking the ground is a good idea anyway, but the culprit is the connector.
You just need to remove the console again (!), pull the connector from the cluster and check those contacts. They're made of soft metal, and they tend to "flatten", losing contact with the "trails" on the cluster side.
VERY VERY carefully, try to bend them a little outwards so that they can firmly touch again the cluster's contacts.
And in case you're wondering, the clock works because it only needs +12V and ground, and the vacuum is mechanical, so it doesn't need power at all. In my case, the +12 and ground contacts were good enough, but the other ones were loose, so I had poor or no battery and oil press. readings. Well, I needed a new pressure sender too, but that's another story