Chrysler Sebring 6-Disc CD Changer and Aftermarket DVD Player

A friend has a Sebring with a factory 6-disc CD changer. The system also has the steering wheel controls. He is considering having installed a remote screen DVD-CD-MP3 player, but he is concerned about two things: 1) Will installing the aftermarket DVD player negate his use of the factory 6-disc CD system and 2) will he lose the ability to control the new system with the steering wheel controls? Ideally, he would like to have the factory 6- disc changer working with the new DVD player and the steering wheel controls functional for both. Thanks!