78-80 C10 Big Ten Driver or Passenger Side, GAS, 20 Gallon, Ahead Of Rear Axle, 56 x 14 x 11, Lock Ring Kit Included. 75-80 C10 (submodel: Cheyenne, Custom Deluxe, Scottsdale) Driver or Passenger Side, GAS, 20 Gallon, Ahead Of Rear Axle, 56 x 14 x 11, Lock Ring Kit Included.