Ok, what dad told me was that the Chrysler 12" drum brakes had one wheel cylinder per shoe. Unlike like Ford and General Motors using one wheel cylinder per wheel.
The weight of the car as dad had it was 3,000 pounds. From 60 mph to 0, he got the car stopped in under 200 feet without skidding. Discs might be great for other people for their cars, but for me and mine, I'm keeping what's on it.