Rare Dodge Dart GT? Which engine is this?

Exactly just as the rest of the car. It could totally be something "rare" as we've seen no fender tag. Being what it is over THERE really makes it somewhat rare already! But race engine? Nah. Thing about it is, Even a stock small block in that would give a GTO what for.
Like the alternator on the drivers side. It looks like a cast bracket. Nothing close to ours here in the states.