what setup do you have? is the radio a double din device with the tape deck mounted in it's own pocket above the cubby hole? most times you can buy a cable or device that plugs into the changer port (provided your radio has this capability; look for the button on the face) to create an aux in using rca connectors and allow control from the headunit. however, it seems like the changer port is already occupied by the tape deck and there is not another port on the tape deck. your options would be to loose the tape deck, go with another method (like rf modulated or another tape adapter), or rig something up where you can use both.
http://handa-accessories.com/accord/...cassetteex.pdf
http://usaspec.com/files/IPODAUX-Application-Guide.pdf