Are you sure your brake lights are not actuated by a simple limit switch on the pedal? I am not sure about a Rambler, but most cars of that era just have a pushbutton switch that closes when you move the pedal arm. Check your fuses, too - often just a blown fuse takes our the brake lights, and the factory sometimes wired something else into the circuit to get your attention, like the dome light staying on 1/2 power on early 70's Chrysler products to alert you to something being wrong.