OK,I am wondering if anyone out these has the definitive answer about changing the XM brains in the new Camaro to a Sirius brain. I have a Sirius lifetime subscription because of Howard Stern, but I ordered my 2SS despite the XM standard. You would think that since the merger they would make it optional which you wanted in your Camaro, but no. I'm not sure the antennas are cross-compatible... does anyone know the truth about this? Please help!