Grounds. Go through all your ground points and clean and apply dielectric grease to them. The ground for the dash lights is under the dash between the steering column and the center dash (if I remember correctly) and the ground for the tail lights is in the trunk on the driver's side (left side). While your at it, clean all wiring connectors (particulary the tail light connectors), fuse holders and bulb connections and apply dielectric grease. I did this 10 years ago with my '82 and have had no failures.
