If you prefer the rear Aux In over a front Aux In connector, you can buy a right and left (white and red) RCA connector that adapts to a 1/8 inch male stereo connector....which would plug
directly into your iPod. Radio
Shack sells them along with many other electronics
Or if you prefer to use the front AUX In connector then get a 1/8 inch stereo male-male connector.
I purchased a stereo for the boat I work on which had the option of buying
the cable which goes directly from the back of the head
unit into the bottom connector of the iPod. It takes over the iPod interface. The problem is that the head
units user interface is horrible. It also does not charge the iPod. Perhaps there are head units with cables
out the back that do charge the iPod and have a nicer user interface?
I just bought a Fusion unit for my personal boat where you place the iPod inside the head unit. The user interface is wonderful, the iPod is completely protected from moisture and the user interface I think is almost as good as the iPod's user interface. You can also buy a wired remote
for installing at the steering
station or wherever. I bought that as well. I am really happy with it. Its much better than the somewhat comparable Sony unit.