When doing replacement or upgrading on 1980 – 1991 Volkswagen Vanagon, the bulb size guide is necessary for you to take the reference.
Jump to corresponding car model with the catalog bellow.

High Beam and Low Beam Headlight1986 – 1991 9004
1980 – 1985 H6024
Front Fog Light1986 – 1991 H3-55W
Back Up Light1980 – 1991 1156
Brake1980 – 1985 1156
1986 – 1991 1157
Dome Light1980 – 1991 578
Front Side Marker1980 – 1991 T4W
Front Turn Signal1980 – 1991 P21/5W
License Plate1980 – 1991 T4W
Parking Light1986 – 1991 1157
1980 – 1985 P21/5W
Rear Side Marker1980 – 1981, 1983 – 1989, 1991 12929
1982, 1990 T4W
Rear Turn Signal1980 – 1991 1156
Tail Light1986 – 1991 1157
1980 – 1985 12814
Center High Mount Stop Light1986 – 1991 194
Courtesy1986 – 1991 6411
Glove Box1981 – 1982, 1988 – 1989 12818
1980, 1983 – 1987, 1990 – 1991 DE3175