...remove the tool tray in the left cubby and look up and to the right of where the tool tray was. There should be a black cable with a round 13-pin connector tucked in there, probably covered with a small styrofoam sheet. It is just zip-tied (actually a "ladder" style tie) and can be used for the Phatnoise.

As far as your wheels, it depends on the size, offset AND the shape of the spokes. What wheels are they? Do you know what make and model? Any specs???

SOLD!!! OEM RS6 Wheels 18x8.5 (set of 5)
SALE PENDING: OEM RS6 Grilles (uper and lower)
FOR SALE: OEM RS6 rear bumper inserts