You can do it yourself, if it is sat ready then there is an input more than likely on the back. Pull the radio, you can get the removal tools from Wal-Mart, then look for a line input. If there is not one call the local radio shop and ask how they get it in. No Ford dealer that I know of does their own radio work so ask the shop if they do the dealers work.
I just added XM but I used am FM modulator because my radio does not have an input. The only problem I had was the XM was 6 volt so I added another power plug under the dash then plugged the power unit in there to hide it.