64 Viper Dart??

Ok, I am a new member here, and I would like some input from you guys. I have had my 64 Dart with the original 170 slant-six and 3 on the tree since high school. After and unfortunate man-hole/ K-member incedent, the car has pretty much sat in a garrage and now a storage unit. I am now getting to the point that I either need to do something with that beautiful machine or sell it. I have always had this crazy dream of stuffing a Viper drive train in that car. I haven't heard of any one doing that in an early model A-body yet. I am not sure if that's because it can't be done or it just hasn't. I have already found a motor and tranny that I could buy, but before I do I am curious if you guys can think of any reason that I should just go the easy route and drop in a small block crate motor?