Disappearing Fuel Level

Very odd.. fuel sloshing?
Any chance you are seeing the instrument cluster voltage regulator it goes on and off at some frequency?

Lol definitely not sloshing, the car doesnt run for other reasons. The neighbors don't appreciate me trying to get it to run at this time of night, so I'm working on other things.

I'm starting to suspect the VR as well. I have 55 ohms on the sender wire at the back of the cluster which is reasonable. I should add that this cluster in a unknown item. It never had more than the speedo connected prior to this attempt. All I really want is the fuel gauge and the signal indicator and speedo lights would be a welcome bonus. Thats a topic for a different thread maybe as they should be mostly separate circuits.