and all 73 -87 C and K model Chevrolet and GMC truck VIN#'s deciphered. For Silverado, Cheyenne, Custom Deluxe, GMC Sierra Classics, Chevy Scottsdale, Chevy Blazers, Suburban, GMC Sierras, GMC Suburban, GMC High Sierras, GMC Jimmy, and more... Motors and transmission and transfer cases...