Does anybody know if DEI Remotes are compatible across their product lines? Like Viper and Clifford? I have an older G4 Clifford alarm in my car. I want to install the Viper 3002 (or similar) in my wifes new car. But.. I want to program both remotes to work both cars. So, my Clifford remote button 4 would unlock my Wifes car, and her Vipers remote button 4 to unlock my car.