I want to install a CD Changer in my 1996 Standard 850 Wagon with a stock SC 710 radio. Can I tell if it is pre-wired for the changer (the radio face has CD controls). Where exactly does the CD changer fit in teh back? I know that I need to buy a specific Alpine Changer as well as special wiring harnesses and connections. Is it possible to swap out the stock radio for another model that has a single CD slot in the deck? Does anyone know where I can get one without spending too much money? Thanks for your help!