Looks like the 1970 C60 Air Brake units were only available with the 427 engine. They had a 6.71/9.14 ratio, 23,000 pound rear with 15x7 rear brakes and either a 9,000 or 11,000 pound front axle.
Mike B
Mike Boteler
1956 Chevy 3100 Resto Rod 1952 Willys M38 Army Jeep 1983 Jeep CJ7 Laredo 1984 Jeep CJ7 +++++ Silver Spring, MD