don't just cut it, if the factory head unit is out then all the wiring will just be loose behind the deck, take the glove box out and the trim behind it and remove the wire and the antenna, all the wiring to the gps unit in the trunk goes through cable trays under the carpet on the left side of the car and is reasonably easy to remove. There is no need to remove it though, other than cosmetics of loose wires behind trim, or the fact that you know that it is messy under there. if you have a phillips head screw driver you can get it all out. (i just wound mine up and cable tied it near the battery in the back!)