From my 1955 Buick service manual (which is excellent) --
"The brake assembly at each wheel uses a primary (front) and a secondary (rear) brake shoe of welded steel construction with one-piece molded lining attached by tubular rivets. The primary shoe lining [front] is shorter than the secondary shoe lining [rear] and is of different composition; therefore the two shoes are not interchangeable."
1955 Super (model 52)
(Factory power brakes, power steering, power windows, and power seats ... Aftermarket bondo and blood.)
Wanted: "Driver" quality front & rear 55 model 50/70 bumpers.