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All 1964-66 GM cars had drum brakes. 1967 was the first year for disc brakes; both 1967 and 1968 used dual piston calipers. 1969-74 all used the improved design single piston caliper. All brake conversions use the single piston caliper and will fit all the 1964-72 GM A-Body cars. This includes: 1964-72 GTO, LeMans, Tempest, Chevelle, El Camino, Monte Carlo, Skylark, Gran Sport, Cutlass, 442 and F-85. These kits will also fit all 1967-69 F-Body and 1968-74 X-Body cars. This includes Camaro, Firebird, Trans Am, Nova, Ventura, Apollo and Omega.

Sources: [url]http://www.inlinetube.com/disc%20brake%20conversion/dbrake.htm[/url]