Usually it is somewhere in the drivers side door frame. The tag is 3.25 inches long, and if it has been removed there will be two holes almost 3 inches apart. 66's are at the very top, 64-65 are upper door frame (on the A-pillar). Crew cabs have it in the rear drivers side door frame sometimes. If this doesn't help, the VIN verification departments of the State Police have diagrams where EVERY VIN is located on every vehicle type in the USA.
The one on the frame doesn't have the first few digits on it usually. It is located next to the driver's side motor mount. Use a wire brush to clean it off.
