I'll start with basics... 1997 Regular Cab Dakota, V6, 4x4. Over the weekend I replaced the rear bumper and brackets (old one was starting to rot out). After doing so, I started up the truck and turned on the lights just to make sure the tag lights worked...they don't. Nor does the rear taillight running lamps. Brake lights work, turn signals work, headlights work, front running (corners) lights work. Absolutely no blown fuses whatsoever, I check all fuses in dash panel and the panel under the hood. Everything in the cab still works, i.e., radio, cluster, dome, etc. I checked all the connections for the taillights and plate lights both at the lamps themselves and at the harness. Checked all the bulbs as well, all tested good. I'm ready to pull my hair out. What could it be? Where are the grounds that I should be checking next? Or could it be one of the trailer relays? To say the least, I am out of ideas...please help! Thanks in advance!!!