Lost all electrical, then it came back. What's going on here?

Rusty, before I installed the rebuilt motor, I very carefully cleaned and filed the eight female cavities in the connector at the bulkhead disconnect on the engine side. I then hit all eight cavities with electrical contact cleaner spray. So I'm thinking that there was not a lot of electrical resistance there because I cleaned it up really well. Whaddya think?
Maybe. It's still worth inspecting, since it is easy to do. I would also inspect the connections at the ammeter as well as the welded splice behind the cluster. .......and ALL grounds. Even the battery terminals.