Engine Bay wiring

Most of the engine wiring is in place now, even got the clutch and brakes bled after the new pipes and slave cylinder were fitted.

But stuck on one thing. There are two earth? (Black cable with bolt down end crimps) wires which come out of the chassis in the engine bay down underneath the brake servo. The wiring is muddy as looks like it hasn't been connected to anything for a while.

If they are earths I don't suppose it matters where I bolt them to. But it would be nice to put them in the right place.

Cheers.