I have not done it yet as my 328 has yet to be delivered. I'll be going with a mini as we happen to have one. Dual Bluetooth GPS antenna. Will be used for nav only in my install. My thoughts are buy a RAM holder and mount it to the existing display with a simple slip on, tight fitting, "glove". UPDATE: Sent the RAM back, too big. It's not permanent as I usually use my phone for nav and the mini is just for long trips with voice directions coming from the internal speakers.
Other approaches which may work for you are a cd tray mount either facing up or down. There's a Korean one sold on eBay that I felt had the best approach, forget the name. Or a ProClip, which I did not like as one does not want to take it on and off often.
UPDATE: Tried the USB out from the Camera Connection Kit. On the 3 iPads we have, we get digital music out. For the mini, works with the lightning/31 pin adapter. Do not know how well the controls will interface with the BMW. The BMW dac will likely trounce the iPad's so, if I decide to do music, this is the way I will go and use the mini for control.
Last edited by threeOh; 04-22-2013 at 12:20 PM.