You will need to loosen the pilar that houses the tweater. There is a screw behind the airback label. Unscrew that, then loosen the visor screws and you may also need to loosen the overhead consol screws. Gently pull the headliner down and feel for the wire from the existing visor that plugs into the harness in the headliner.I would like to upgrade my 2006 CTS with a sun visor that has a garage door operner on it. How do you change the wiring to it. Does the wiring unplug at the holder or in the roof liner?