Interesting Topic and it's right up my ally.... I've just got the iPad mini (3G) purely for car use (i have Ipad3 and iphone4S) and I'm picking up my 320d when I get back from my work in Denmark. It has the basic stereo in it which is what I wanted.
I'm tempted to buy the Connect2 double din facia and modify it to house the ipad mini, but I'm a little concerned about a few things.
1. How to mount it so it's flush with dash and still be able to power it. I'm pretty good with fabrication so that will just take time. (Stock HU will be moved to the Boot). I think it will have to be slide loading with the bezel able to "eject" to retrieve the ipad mini when not in use. Don't want those pesky thieves breaking in if it's on show.
2. Where to get the power (USB) from - I'm thinking of taking apart a 12V USB cigarette adapter and connecting the 12V supply off the wiring for the cigarette lighter (this will keep the internal fuse of the usb cigarette adapter in the circuit-safe guarding the ipad from over current)
3. Moving the AC controls to the Ashtray - this is because the of the Ipad mini's width (134.7mm) compared to the facia opening "double din" length (108.6mm). This means the ipad would never fit into this facia unless I move the AC controls. I've seen this done on here but can only find pictures but no write up.
4. What is the best way to connect to the HU while still keeping the steering controls. Is this done thru an ipod aux box
I need to research this further some points further but any initial help would be much appreciated.
The Difference between Genius and insanity??............. Is the measure of success!