I have a 1969 Mustang 351, I was just wanting to know if anyone can tell me how I find out if it is a matching number car.  Would appericate any help.  Thanks  

While today's VINs are relatively standard, there was no standard with VINs, or any other numbers, with older cars. VINs, (formally called a serial number) came in all sorts of variations, which depended on the individual manufacturer at that time.

Car parts are stamped with several numbers at the time of production to verify the essential facts about the car and also to assist in manufacturing sequence. Some cars will have a significant identification plate, listing the major part numbers against which you can check. Depending on the make and model, you may find these numbers stamped not only on the engine, transmission and rear axle, but also on the alternator/generator, carburetor, distributor, water pump and heads.

When buying or selling your classic, finding out what numbers you need to verify and where they are located on the vehicle takes a diligent “Sherlock Homes” type. It can be a bit frustrating even for the experienced classic car buyer. If in doubt, contact a professional who knows that particular model car to either check the numbers for you or assist you in finding and interpreting the numbers. Good resources for such information are the many model specific clubs; their members are usually knowledgeable about their cars and very willing to help.

Depending on whom you talk to, the definition of a “matching numbers” car may vary. A classic car purist might say that a truly original, matching numbers car will still have all the parts that it was manufactured with, including the tiniest nut and bolt. That would be very hard to find in an older car, so a more practical definition might be that all the parts will be either from the assembly line at the time of production or have been replaced with authentic NOS (new old stock) parts.

The most general use of the term “matching numbers” would mean that the engine and transmission are marked with the same sequence number as the chassis VIN number, and the rear axle/differential’s date code and casting number corresponds with the vehicle that's being checked.

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