[PonchoV8]

Tires are produced with a code that contains a date in them. It should be easy to determine if it's an original tire, because there is a DOT number molded into the tire. I have one that I believe came from an original Y88 TA and here's the DOT number. The last digit is the year. The three numbers in front of it are the julian date. A date of 0179 is the 17th day of 1979. Or it could be a date of 1989 or 1999. The thing is to determine that it's a correct setup and then look to see of the date coincides with the build date.
the white lettering on the exterior of my tire is mostly gone. There is some left in between the treads, but it looks like it has been run a little in the past.
This tire was built the 9th day of 1978 and the car was built March of 1978. It's a BFG tire. There is only two digits before the 8 because it was built in January I assume. Look at tires on any car and the date can be determined by the DOT #.