didnt have any factory wiring in my 1999 gti, open near your 1st aid compartment and have a nosey about if there aint any plugs i assume these no factory wiring, i got a sony 6 disk changer and interface and ran the leads up the left hand side of the car under the carpet and it plugged straigh into the back of my vw gamma raido cassette (which i wanted to keep as it matches all the dash lighting etc), if your fitting one of these youll have to unplug your single cd unit (if you have gamma and single cd above) to plug the changer in, id ditch the single unit and get the cubby hole bit to fit in its place, about ?15 from vw, hope this is of some kind of help