14 March 2016

Ford Mustang by the numbers: Researching original equipment

Ford has sold more than nine million Mustangs since the car’s April 17, 1964 debut, and over time many of the surviving 1965-73 Mustangs have been modified from their as-built specification. Fortunately for owners who wish to know exactly how their cars came from the factory, there are several resources for looking into a car’s past.

When needs go beyond visual cues – for instance, a 1969 Boss 302 will not have the quarter panel scoops that other Mustangs carried – there are many publications and sources for determining Mustang factory specs and matching parts numbers.

The most-utilized and viable guides come from the work of Kevin Marti, a licensee to Ford Motor Company’s entire production database for the 1967-2007 model years. His records have made Marti Reports – detailed accounts of an individual car’s original equipment – an essential link in verifying a claim of matching numbers. Marti has also published “The Mustang and Cougar Tagbook,” which provides decoding information for data plates, body tags, engines, transmissions and carburetors for 1965-73 models. Marti’s “Mustang by the Numbers” contains production facts on Ford vehicles and over 12,000 statistics for the 1967-73 model years.

The 1965-69 models have a metal door data (or warranty) plate, which changed to a Mylar vehicle certification label for 1970-73. The data plate includes codes for the body style, exterior color, interior trim, scheduled build date, transmission and axle ratio. The VIN on the door plate should match the VIN stamped into the driver’s side inner fender apron, and it should also match the windshield VIN tag on 1968-73 models. Experts can spot whether or not a data plate has been replaced by checking the rivets.

Matching an engine to 1965-67 Mustangs can be a bit more challenging due to the lack of engine and transmission tags, with the exception of the 289 Hi-Po model, but it is still possible to find out which engine a car should have via the engine code listed the VIN. Thankfully, that difficulty was realized and Federal law began requiring the stamping of VIN numbers on engines and transmissions beginning in 1968. And since the VIN includes the engine code, a quick check for a matching numbers engine can be simple.

For example, a 1966 Mustang with a later 302-cid Windsor V-8 engine would not be a matching numbers vehicle. But just because an engine is missing a tag, or the numbers are unreadable, doesn’t necessarily mean that the Mustang is not a numbers-matching car; it could be that the engine had machine work when it was rebuilt or that the engine stamp wasn’t aligned properly at the factory. Complicating things further, door tags are often removed or painted over during restoration.

If you want to dig deeper into the matching-numbers realm, casting or engineering numbers are another way of identifying factory parts, and nearly every component, even a headlight housing, can be equipped with a tag or stamped number. While the correct casting number on a part doesn't prove that it came with the car from the assembly plant, it can at least verify that it is correct for the year and model of car.

7 Reader Comments

  • 1
    J. Boulger Pebble Beach April 4, 2016 at 15:28
    I have a 68 Mustang convertible which, when painted, the metal tag was removed and not replaced. I am the original owner and also have the original purchased papers and need to have new metal plate made to be installed with all the proper information as I want to sell the car. Any one who could help me ???
  • 2
    Sandra Bennett Thistle Cove Farm, VA April 4, 2016 at 16:28
    Thanks for this fabulous article! My red convertible '67 Mustang, with the exception of tires, is all original and it'll stay that way. Why mess with perfection?
  • 3
    jerry dybevik United States April 4, 2016 at 18:43
    I have a 1965,6 cylinder, I believe a 200 engine.but there's a tag on the valve cover that looks like it came from a 1970..can that be possible?the block #'s I've found looks like the engine was built in August.if I'm reading them right.
  • 4
    Clay Lompoc CA April 4, 2016 at 21:55
    I found the door on my 65 GT had been replaced and thus the door tag didn't have the correct info. I bought my car from the original owner who kept the car original, but the build date was in question. I used the following website to determine when my car was built. http://www.isomustangs.org Keeping the Mustang original is more satisfying and allows you to appreciate how much power the 289 with 4V carb could produce. And it's fun! Would still like to find someone who could provide original build sheets.
  • 5
    Jay Armshire Bayville, NJ 08721-2211 April 4, 2016 at 23:03
    How do you find out information about the build sheet, which has a lot more information then is on the door plate?
  • 6
    djrodgers Alabama April 11, 2016 at 14:32
    I received a 1967 390GT for high school graduation. Odometer reads 72,500 miles. All sheet metal, glass, drivetrain, seats, headliner are original. Only addition are period correct style steel wheels, which were bought from a local body shop before they were junked. My husband drilled the rivets out, pressed the rims off the hubs, re chromed the hubs, pressed the back together, re riveted and trued to hi standard. Car was restored in 1982 then again after a tornado junk blasted the body, 2011, but no damage to original sheet metal. Been married for 47 years but had the car longer than the husband. Any guess which I'll keep as long as I live!!!
  • 7
    Kelly Calloway Kingsport, TN April 10, 2017 at 14:45
    I have a 1965 mustang and have researched about matching numbers. I found at some point that with the build sheet it would tell what the car was born with. If the car has the same motor , transmission and rear-end that it was born with it is a matching numbers.

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