People have done it John, but it is a little bit more involved for Chorus owners. As well as the RNS-E unit, you will to strip out the entire centre of the dash and fit a double-DIN cage, plus either cut your existing climate control panel to fit it lower in the dash (using a dremel) or buy a new climate unit (expensive). You may also need some new buttons for ESP and the passenger airbag warning light.Agree with Steve though - the
http://www.navplus.us is fantastic and full of information on the RNS-E. I used it extensively before my install.