Re: Crap! Brake lights have not been working for n
Check each of the wires to chassis ground. One of them should read 12v. Although checking to the other wire may show 12v it's not showing you if the circuit is ok.
The tail, stop, reverse, and turn signals all have the black wire attached to the lights grounding at the same point as the fuel tank sending unit. 73's and up also had the rear window defrost grounding at the same point.
Also do a check on your stop light switch. Just put a continuity meter on each of the two wires coming out of the switch. If you register a circuit, i.e. continuity, with your foot OFF the pedal, you might need to adjust the switch. Depress the plunger on the switch and see if the light goes off. If it does NOT then your switch is bad.
If however you aren't getting power from one of the wires to ground, then you need to check your fuse. Also check the condition of your hazard switch, as the stop light switch also connects to it as well as the turn signal switch.
My 2¢