Classic/Antique Car Repair: 1957 chevy truck, Brakes, brake pedal

Question
you really did not answer my question about the brake pedal spring.since the only thing that has been alterd is they went from a manual to a automatic ok, so all there is isa brake pedal ok. iam esing the same single stage master cylinder, but where does the tension spring mount to put tension on the brake pedal and where can i get one classic catcloges do not carry one

Answer
Do you have the wide brake pedal like in most automatic transmission cars or the narrow one like in a factory standard transmission? Also is the pedal suspended from the fire wall/steering column or up through the floor with the master cylinder under the floor?