Ok short story, 01 X5 tape deck, premium sound/dsp/6 disc changer. Would like to get rid of the tape deck and get a cd player installed

This is the model i'm looking at and am told by the seller that it will fit

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=5777010504

I have asked about the round / flat pin conversion and they are providing the adapter. First question is, is this correct and will this work? Second question is currently I do not have an AUX port and this says that it has one, would that add one for me? For an IPOD or Sirius? Or is it used by the CD changer. Thanks Andy