70 Rupp Roadster brake/tail light question

[novadose74]

I have an after market brake light. I have an original harness with the two wires, one black, one brown going to the taillight. Which is the brake light, which is the taillight? Thanks.

 

[Mariah]

The easiest way to find out is to hook a battery from the metal taillight housing to one wire at a time, dim is tail...bright is stop.

 

[ruppking]

Brown wire is brake light

 

[novadose74]

Thanks. I got it working perfectly.