ipod into sony MP40 in a 04 ws lsv

I just purchased an Ipod, and i love it, and i want to plug it into the stereo in our BU. I have a cable that takes the head phone plug and turns it into the rca plugs the red and white. Should I beable to plug it right into the stereo or is there a better way to do it, where i could control the ipod from the stereo? Also how do I get to the back of the head unit, we have an 04 ws lsv.
Thanks

Chris