Base Audio Non iDrive Head Unit Wiring

[King Tut]

I have ordered my 2009 M3 with the base audio and without iDrive with the intention of replacing the head unit when I get the car. Now currently I haven't been able to find anyone who makes a wiring harness for the car due to it being a fiber optic cable. I thought that the fiber optic cable was only used on the upgraded audio like it was in the other 3 series with the Logic7 upgrade. Has anyone pulled out their head unit or can someone confirm this? I know there are some guys out there with aftermarket head units so how did you get around this? Thanks.