I was having problems with the tailights on my 67, intermittent problems with the worn out sockets, etc. I just replaced the old harness, with a new one from Rick's First Gen. It went smoothly, exactly what came out, went right back in. The problem now is the left rear brake lights don't work at all. Everything else works fine but the brake lights on the left side. Can anyone give me some guidance as to where to start to troubleshoot?
Thanks. Dan Z. (deezee)

Make sure you have a good ground. I had the same problem with my 69.