Part Type: Drum Brake Wheel Cylinder. 1968 Chevrolet Chevy II Bore: 1.125 In. Position: Front Left;. Manufacturer: Dorman. Position: Front Left. Brake Component Inlet Thread Size: 7/16-20 UNF. To confirm that this part fits your vehicle, enter your vehicle's Year, Make, Model, Trim and Engine in theCompatibility Table.