Electrical Troubleshooting help please

[Fast67VelleN2O]

I am having an issue with my 1967 Mustang Fastback GT. When the ignition is off the tail lights (not brake lights), license plate lights, and dash cluster lights stay on. (This is with the light switch in the off position). I went out and bought a new light switch, thinking that it could possible have been the problem as it was the original switch. Plug it in, still the same problem. When the light switch is completely disconnected from the wiring harness, the tail lights and license plate lights are still lit, however, the dash lights are not lit anymore. Car is all stock, all nice original Ford wiring. Any suggestions?