I know this has come up a few times where people were looking to see what the Mexican built cars were like. Here's a link to a current Ebay auction of a Mexican built 73 Mustang.
eBay Motors: Ford : Mustang (item 160223917013 end time Apr-04-08 16:53:10 PDT)
Not my car for sale, 'nor do I know the seller! I just want to point it out if anyone is curious as these cars don't show up very often.
Some points to notice:
Speedometer/odometer in kilometers
Spanish door tag
Spanish decal on air cleaner
Spanish fan shroud
VIN number codes different than American built cars.
Round snorkel on air cleaner base
Note: the driver's door isn't original to the car. That's why it has a sticker with a DSO of 17 under the original stamped metal tag that the original door had and someone removed and transferred to the replacement door.
Just thought I'd share.

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1968 Mustang coupe, Acapulco Blue, 289 2v, C-4, Power Steering.
Hopefully a 1969 convertible or Sportsroof (non Mach or Boss) for next Mustang project
Trying to find my father's 1973 Mustang Grande he bought brand new. 3F04F126773 last known registration and title was in New Jersey, 1982.