Alright....here's another thought.
My Galaxy S3 came with a cord that hooks the phone up to a USB port.
I'm thinking that if I use this cord to plug the phone into the USB port, that simply hitting AUX will automatically have the car playing the music on my phone, as if I had a flash-drive plugged into the USB port.
Or, to make things easier, I'll probably just re-load my music onto a flash-drive I have lying about.
Hell, I'm bored, gonna do that right now.