ipod ford 5000 head unit + auto changer

No need, just purchase one of the recent FM ipod transmitters from Belkin or the like and tune your FM radio to the chosen frequency. The use of these was legalised about a week ago and they appear to work very well.

Mike

Except that there is no single frequency that will allow you to enjoy your iPod music as you drive around the country. The more built-up the area, the more likely you will find yourself listening to some annoying pirate station instead. Even 87.5, supposedly below the official UK FM band, is occupied in places like Slough, Birmingham, and large parts of London.

A direct connection to the head unit is much more satisfactory.

Plus it charges your ipod at the same time, which is naturally a bonus, especially if you have an earlier generation model of ipod.

Big minus is that with FM transmitter you have mediocre FM quality...+ noise from neighbouring stations.