Battery Earth/Chassis Bolt.
From this earth bolt there are two other earth cables going to the earth bolt on the passenger side chassis earth bolt.
If this earth bolt is "Not Good" then the earth path, for the starter motor, will go through these cables and burn out the loom to the opposite chassis.
On purchase of this vehicle the earth bolt was rusted, almost through. This area was renovated, a new bolt fitted and then painted with "Hammerite" paint.