I have been told multiple times that my taillight issue could be a ground problem. I traced the black wire up until under the dash by my switch panel. I was told there should be a black ground wire attached to metal. I have been unable to find this wire. I have always had the headlights when I turn the switch on. The brake lights are working how, but still no taillights. I have switch bulbs and clean the light socket. Also I tried to take the switch panel but when I unscrewed the bottom screws it seems that the top of the switch panel is still caught on something. Is there another screw underneath?