1968 Chevrolet C20 Pickup Engine: 6.5L V8; Standard Rotation|Standard Duty Thermal Fan Clutch;. 1969 Chevrolet C20 Pickup Engine: 6.5L V8; Standard Rotation|Standard Duty Thermal Fan Clutch;. 1970 Chevrolet C20 Pickup Engine: 6.6L V8; Standard Rotation|Standard Duty Thermal Fan Clutch;.