I have a '69 convertible GT. It's a great car and lots of fun. Hope everything works out for ya! I will agree that it's a little weird that the car has a C6 with a 351. I have an FMX, and I believe all 351's did as well. As for the dual exhaust, I think that all GT's had duals, and I know that you could get a 351 2v in the GT, thus the duals are probably original. Its probably got the FMX in it, but you may just want to verify that. I wouldn't worry too much though, even a GT clone is bringing a ton of money. If it turns out not to be a GT, just be happy you found a 351 convertible.... almost an impossible task these days. What is the asking price?