If you buy a HD from Crutchfield............you have to hookup the speaker wires from the new head you CANNOT use the rca the sound will be real low. Crutchfield did supply the plug with wire hook up no rca so if go to Crutchfield tell them if it's a coupe or roadster. The rca's are for the infinity system only. Sorry these are the facts. Don't believe me??????????? check with Crutchfield