What's the best, inexpensive way to get the music on my iPhone to play through my car speakers? I was looking into bluetooth car decks like some cars come with, but they seem to be hard to find and not many available. Should I just get a car deck that has an AUX jack? Also, how difficult is it to replace a car deck? I already have a custom 1 DIMM car deck in my car right now and would like to save some money by doing it myself. Plus, it seems a little silly paying Best Buy $50 to install something that would literally take them minutes to do. Thanks!