[Aircobra101]

also working on the loom adn trying to work out how to ground the harness. its pretty clear that the positive comes through the white wire from the battery
under the dash, there are 4wires - 3 black ones ( presumably ground ) and a white one
the previous owner rigged up some sort of a redneck kill switch - and that is where the fat black one goes. it just grounds the fat black wire against the dashboard
see photo
question is
1. looks like the 2x thin black ones connect to the firewall. but i'm not clear how they would make a good earth
2. what's the white wire for?
3. for the fuel tank sender, where does the ground connector go?
also looks like they're a bunch of spare bullet connectors around the dash. would they be for the seat belt wiring lights for the us model?