The earth wire for the headlights is bolted to the closer plate, just below the radiator hose, and the closer plate is bolted to the front crossmember of the chassis.
I run a thick earth wire internally from those earth rings by the radiator hoses, through the footwell, past the fusebox, and earthing to the chassis via the bolts holding the brackets at the bottom of the dashboard to the chassis, so the earth is not affected by external rust and corrosion.