Do like I did; drop the car to a car stereo specialist, leave him the car key, and go shopping for something else for the wife. Takes 3~4hrs and <$250. More if you want to change the speakers and amp I'm guessing.
Few options to look into; either using "analog-to-optical adapter" in the 12vdc ($25~$500). I think this is if yuou want to retain cd charger feature only, could be wrong.
or the back alley kit for a stomping $1,499 lolll
Porsche w Bose Premium Amp Stereo Radio Wire Harness | eBay
Alpine are great electronics
does what it does anyway