So a few weeks ago, I was trying to install a set of subwoofers into my truck(2001 Blazer LT 4WD 4Dr). While looking for a place to go through the firewall, I came across a grommet under the brake booster. I couldn't pull it back, so I decided it'd be a great idea to try and drill through the rubber. Needless to say, I got through, and I felt the wires on the other side and they didn't feel damaged, however since i did that, my right tail light has been out.
I do know that the socket and bulb still work because the light turns on when i hit the brake.
I'm almost positive it's the harness behind that grommet that is damaged, I just dont know how to get to it to remove or repair it.