The Demon was a RV-2 and now has a SanDen compressor with a Performer. The physical differences in plumbing are the hoses to the compressor and body. The SanDen mounts at the water pump and has an L-shaped bracket at the rear that bolts to the intake. There was no need to change the water outlet on the intake. The hoses I got with the SanDen compressor will not bolt up to the corresponding connections that are in the car..
The 66 Dart GT w/factory a/c had a manifold water outlet that pointed at the driver's side fender, where the non-a/c outlet pointed straight ahead. Someone else can jump in, but I think that once Mopar went to a vertical water outlet, all of the bends were made by the radiator hose. A/C and non A/C cars used the same outlet.
In swapping the compressor, you may have to go to a later model upper radiator hose. You also may have to re-route the heater hoses. There may be some additional changes needed if you're going from an R-12 to a R134a refrigerant system.