If you have the Regal's single-exhaust crossmember, it can be easily modded to work with dual pipes. You'd need a torch or plasma cutter to cut a "semi-circle" out of the bottom side of the crossmember to clear the driver's side exhaust pipe. You can leave it at that and it will work great or you can invert the cut-out piece and weld it back onto the crossover to create a tunnel for the pipe.
Been There Done That - HTH - Jimmy