Changing the right rear foot peg holder to one from a Classic is a 'bolt-on' job after which any exhaust made for a Classic will fit the Drifter. It may not be easy to find the right rear peg bracket from a a Classic so you could just fab something up. OEM classic bracket is nice though as, unlike the drifter rear peg bracket, it has a rubber exhaust isolater. Why the Classic got that and the Drifter did not is a bit of a mystery.