The VIN is located in four places
1 the dash
2 the sticker in the driver side door jamb
3 the metal tag on the passenger side firewall (also tells which engine, tanny and diff)
4 and the VIN is stamped into the metal of the firewall itself.
The last one may be hard to read. It is located behind the motor. The numbers are about 1 inch high and stretch for about 1 foot. To see it best take a flashlight with you. If ALL of these numbers don't match something is wrong.
The tag in the driver side door jamb also gives the month and year of manufacture.
Hope this helps.
Kevin