No brake lights

Everrything on the car is chassis grounded. The ground is through the sockets, fixtures,and so on. If the park and turn elements of those bulbs work the ground is probably fine.
One wire at the brake light switch is hot at all times ( check with a test light ). The other wire is hot when the pedal is pressed to close the switch.
From there the brake light power goes up the steering column and through the turn signal switch. When that switch is in the cenetered position the power goes on to both rear lights. Using a test light you want to find that power going up on a off white or tan wire and cominung back down on 2 others ( green and yellow I think ). We dont want the problem to be the signal switch but it often is :(
Good luck