The guy that is selling it says that is hasn't been converted. Although, he doesn't seem to know much about the car. Do you believe it was a factory A/C car? Can you tell by the VIN if it was factory air?
It is NOT factory... but it is a GREAT system! They spend a pretty penny on that conversion!!!! But, and a big but... if you ever wanted to do a supercharger... that compressor will never work because the bracket is not stock, thus not working with any supercharger kit... Good luck!
possibly but it doesnt look like it. it could possibly be a retrofit kit with a compressor from a newer mustang. thats a compressor for a newer car. i dont even think they had that style compressor that long ago. all in all, its not oem