[s-cars] CD player help request

[Patrick Moores]

I purchased both a 4A0 035 111 and a 4D0 035 111 six disc Cd player - thinking one of these could be added to my non-CD player equipped '95 S6. I was told the connector would be prewired and located in the trunk on the right side - found it. Now I'm confused. The CD players have an 8-pin round connector and the connector in my car is a nine wire harness ending in a rectangular 12 pin(2H x 6W) connector. Is this right? How would these two become compatible? Why would the harness in my trunk contain nine wires for an 8pin connector. Please inform me if I need more parts or have the wrong parts?  thank you
 
Patrick
1995 S6