hey, i'm looking to do my first engine rebuild/car restoration, and i can get a 69/70 429 P.I. with a c6, supposedly lol, from my girlfriends dad. I was wondering how to tell if it really is a P.I. and what makes them different from normal 429s. I'm also hoping to put it into a 66/67 Fairlane, and would like to know what problems i should expect to have... any help would be greatly appreciated... thanks