The vehicle serial number is located on a metal plate mounted on the firewall under the hood. It is on the left side on CJ-5, and CJ-6 models and on the right on CJ-3B models. Identification of a specific vehicle requires a prefix plus a serial number. The following chart identifies the Jeep model by the serial number prefix.
Any prefix that is not given here indicates that yours is a special vehicle with differences that are not covered in this guide.
See figure 1