2003 jeep cherokee, cd changer

hello, i've got a customer that wants to put an aftermarket cd changer in his '03 jeep charokee. he's got the factory cd player that has controls for a factory one. as well as a spot in the back to put the cd changer and an amp under the back seat (factory)  i'm wondering if there's a module to be able to connect an aftermarket cd changer to his factory deck. he priced a factory one and it's mor ethen he wants to spend $650 cdn plus $100 to install.Tri County KustomZ

certified installer

If it is a Grand Cherokee, according to my Staub book, Soundgate makes a interface that will allow you to use a Alpine changer.Top Secret, I can tell you but then my wife will kill me.