How do you install a CD changer in Peugeot 407?

I believe that in the back boot there is two side compartments, one has JBL amp with sub woofer, and the other is empty and should have a preparation for a CD Changer.There should be a lead in place. My Peugeot is 407 coupe HDI 2.0 2009 163 sports so I'm not sure if they all has this. What i am looking for is a CD Changer that will match my system, it seems looking on internet there's not much help about this.