most repair manuals have Vin decoder in front of book there are also various parts catalogs available for free that also show how to decode Vin some older ford dealerships should also be able to help i have found my local dealers have the abilities to decode most Vin numbers also the tech id tag on door will give specifics as to trim ,paint and axle some times trans type i currently have an older repair manual for that truck and it does have the Vin decoder in it you may also wish to buy a ford interchange manual there are several in print they will show complete parts usage codes and interchanges, you will find out that allot of parts for different models and years interchange even from cars and trucks and buying the same part for say a falcon versus mustang can save allot of time and money,

Ford, Chevy ??? Also can you post the vin so we can help?