[Mr70]

Dan
AC #6012 is what was originally used on all:
*1967-69 Camaro
*1962-70 Chevy II/Nova

Begining in 1970,AC #6014 was introduced & what was original on all:
*1970-75 Monte Carlo
*1970-81 Camaro
*1971-77 Chevelle
*1971-78 Nova
*1971-77 Vega
*1974-76 Monza
*1976-77 Chevette
This is just for Chevrolet Vehicles.
MANY other car Manufacturers used these same AC numbers in their models too,during those same years.
They are all interchangeable.