Power vs. Manual Brakes
Part Differences Between Manual and Power Brake Cars
Just a word about my observations on the differences between manual brake pedals and power brake pedals.
Most brake pedals have both upper and lower holes for brake master cylinder attachment. The upper hole is for manual brakes, and the lower hole is for power brakes.
Some late 70's and 80's cars utilize a pressed in pin from the factory for either manual brakes (upper hole) or power brakes (lower hole) and a open hole for the other.
Manual brake cars and their pedals generally use a pedal return spring that has one end attached to a hole in the pedal hanger.
Power brake cars do not use a pedal return spring, but many use a brake light extension bracket that is bolted to the brake pedal.
Pedal Hangers (Brackets)
Some pedal hangers are specific to manual brake or power brake cars. With the difference being the hole for the return spring and the brake light switch bracket.
Some models (Mostly Chevy) have welded on brake light switch brackets, and some models have bolt on brake light switch brackets (Mostly Buick, Olds, Pontiac).
Models with the welded on light switch brackets may have more than one hole for the switch. Generally the lower hole is for power brakes.
Models with the bolt on light switch bracket can have brackets specific to manual or power brakes, or upper and lower mounting holes. The lower position is for power brakes.