71 Demon Sizzler

hello,wondering if anyone can tell me the best route to finding all the details about my car.like how many produced in my color ,how many are still known in existence.i purchased this demon in 2010 it sat in a garage since 1978in detroit.the guy was the second owner.there are a lot of strange things I have ran across while restoring it and it would be interesting to find out the history.thanks for any help ,bksgonzo