DID they use the same plate? The A-body radio/heater delete plate was a one piece unit, not like what was on the Barracudas which was a single, simple rectangular plate.
the barracuda heater control block off’s have molded clips behind them that precisely fit into the control slots in the heater control area. And snap in.
One guy with a Mexican GTS showed them to me in his glove box. He had converted the car to heater since the car was in LA. He wouldn’t sell me the clips BTW.