I have a 72 malibu. How does the rear valence attach to the car. Two bolts behind the license plate and then a bolt on each side of the quarters?? If thats it then my car must have had new rear quarters put on because there are no holes on them for the rear valence to attach. Can anyone help me?

Your correct
(2) in the middle behind license plate, and (2) on the ends, that's it !!