You made the same mistake as many other impatient people do...those 325 views DO NOT mean that they are from actual human beings or registered Mac-Forum members.
Does the car stereo specifically say it can support 2 iPods on the same input? You better check on that, as I haven't seen any models that do. There are some that can support 2 devices, but 1 is plugged in USB, the other on a CD-changer port.
OK, just to make sure I understand correctly. You say that your head unit supports 2 iPod inputs, but the cable you propose would in fact use one input.
Every i device has a female socket, so I am not sure what a cable with one male and 2 female is going to do for you. What is the intended purpose of this project?
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