Just bought 03 Maxima SE 6spd with the base CD/Cassette Unit and speakers. Does anyone know if I could simply plug in a factory Bose head in place of the regular head unit? Also, is the wiring in place for the Bose speakers and Sub on the rear deck or should I go aftermarket with the speakers? Do any aftermarket speakers match exactly? (Dont wanna chop up my new ride yet) Thanks in advance for any help and suggestions.