I got my tractor lights rewired. On first try, one out three lite up. I worked with the right headlight until I got a good ground on it too and it lite up. However, the rear light is still a problem. When I do a ground to the reflector, I can get the red light to light up but not the main bulb. I have tried three different bulbs (all new) so I do not think it is the bulb. Plus when I put my tester in there and ground the other end, I get voltage. So something is not working in the guts of the rear light. I assume a bad ground. Any suggestions on how to ground the rear light? Or any other troubleshooting suggestions regarding getting the rear lights to work. Thanks