PIO: The code “PIO” stands for Performance Image Option. In other words, if your Mustang has this code on the tag, it’s a true GT (Gran Turismo) model. GTA models were known for their enhanced performance features and sporty styling. So, congratulations on having a GTA🏁     

1967 Fastback Mustang it has a buck tag, which lists the equipment beyond what is on the data plate It clearly has “PIO” on the tag, which translates to “Performance Image Option (GT).” So, yes, this is a real GTA.     
If your Mustang Fastback has the GT&GTA package, it would be the PIO code stamped on the factory-installed “buck tag.” WOW do you read the article newsletters above... Not only Gran Touring GT" but super rare Buck Tag PIO" True GT&GTA!!! Performance Image Option! It also has the most wanted rare factory rpm! GREAT OPPORTUNITY MY ASK PRICE IT SUPPOSED TO BE AROUND $55K HAS IT IS,  BUT SINCE I NEED TO SELL YOU HAVE A CHANGE TO BUY AT VERY LOW PRICE! The car needs to be repainted and some body work here and there, undercarriage frame is all in good condition, I have the basic 20 dollars martin reports but not show all the options. The car runs very strong and very fast Mustang! Ready to drive everyway let me know if You want to pickup in person and drive Home clean Title in hands.