When doing replacement or upgrading on 1965 – 1967 Buick Gran Sport, the bulb size guide is necessary for you to take the reference.
Jump to corresponding car model with the catalog bellow.

Low Beam Headlight1965 – 1967 H5006
High Beam Headlight1965 – 1967 H5001
Back Up Light1965 – 1967 1156
Brake1965 – 1967 1157
Dome Light1965 – 1967 211-2
Front Turn Signal1965 – 1967 1157
License Plate1965 – 1967 97
Parking Light1965 – 1967 1157
Rear Turn Signal1965 – 1967 1157
Tail Light1965 – 1967 1157
Courtesy1965 – 1967 90
Engine Compartment Light1965 – 1967 89
Glove Box1965 – 1967 1893
Map Light1965 – 1967 89
Trunk1965 – 1967 89