I have a question. I traded some stuff and ended up with a 1970 Trans Am subframe........I think? Is there a way to determine the year of manufactuer? Any stamps, codes, tell tell signs etc?. It does have a huge sway bar and front disc brakes. That's all I know. I was just wondering if a REAL 1970 subframe is worth more because of the 70 being such a "one year" car. Thanks