A couple other items come to mind.
Clean, to bare metal, the contact areas of the VR and body as paint and or other coatings can deter sufficient grounding of any components that require grounding. A couple "star" washers between the VR and body can help. Alternatively a separate ground strap/wire to a solid ground lug. Also maybe add a ground strap/wire from engine to firewall if you don't one have already.
