Check the position of the Power lead on the starter motor.. The starter motor has like a keyway.. If its not properly aligned, the terminal will not sit flush up against the starter motor, and when you attempt to tighten it up, you will break the lug off the starter motor... = NEW STARTER MOTOR (my mate did it) Second of all, There will be a earth point roughly where the ORIGINAL under battery pipe bolted to the engine bay (behind/below the drivers headlight). My guess is 1) you removed it, or 2) you ripped it off when changing the AVO under battery pipe..