Audio Systems: 99 Ford Taurus and CD changer, ford taurus, plug ins

Question
How do I know what kind of harness to get for my 99 Ford Taurus.  I notice on some of these on ebay that some of them have different plug ins. Is there a way to find out a manufacturing number I can use?

Answer
the cd changer plug in to the amplifier that you have in the trunk

http://www.oemautosound.com/pc-42-174-ford-taurus-sable-cd-changer-1995-to-2007....

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=005&sspagename=STRK%3AMESO%3AIT...