Thanks to the help from many here. My 2003 RS6 now has a US-spec RNS-E unit and new XM module working perfectly. All the information posted here guided me through the installation without too many problems. Main thing I encountered was that my Kufatec adaptor was missing the one wire at pin B3 (V-signal) so that I was not making a connection with the speed wire from the spedo. Upon discovering this, the vendor promptly sent me the additional wire which I simply popped into the adaptor and connected directly to the speed wire. Problem solved! Also, my SymphonyII radio was a bear to remove. If the keys were pushed all the way to the "click" the radio would not budge. I found that if I had the keys placed just before they clicked into place, it allowed it to come out. Otherwise everything went according to plan. Thanks to everyone here who helped!