Unless you need the phone for Sat Nav, look at installing a Parrot MKi9200.
Gives you faultless bluetooth and you can stick your phone in the glove box out of sight attached to the connector to charge it. A small remote you stick on your console/dash controls the phone via voice control and the small head unit holds a SD stick with all your music on.
Very good kit and only £150 from Halfords.
features:
• Phone is tucked away out of sight but you still get full bluetooth connectivity so all phone functions including verbal sat nav directions come through your cars speakers.
• Voice recognition actually works; it's best to use full names like 'John Smith' instead of 'Johnnie'
• Noise cancelling microphone that actually works; most people reckon I sound better on the Parrot mic at 70 with the roof down, than stationery on the phone itself....
• The tiny head unit takes a standard SD card ( I have a 16GB in mine) that you can stick all your music on and the quality is excellent.
• You get connectors in the glove box for iPhone/3.5mm/standard USB which means you can pretty much attach anything as well as charge up cameras etc. from the USB socket.