I put a Regal dash in my El Camino, but I also did the turbo motor swap. Still not complete, the front lighting/horn harness and rear lighting harness look like some pinouts need to be changed around a bit. I'm looking for detailed wiring diagrams for both vehicles but no luck just yet. I can tell you that if you plan on keeping A/C you need to swap the under dash ducting over to the Regal stuff too. In the pic you can see the duct and the vent arenot even close.