Steering Wheel

[stranaz]

Hello everybody,

I searched and searched and still did not find anything and that's why I ask here for help.
I'm just in the process to put a Kenwood DNX 9960 into my 2005 BMW and I have two questions.
The steeringwheel has two knobs, one for speaking and the ohter one for radio/phone and I would like to use both of them.
The problem is, how can I find the cables, where are they hidden?
The second question is about the microphone in the overhead aerea.
I would like to use this as well, but also here the same question.
Where can I find the wire???

I would be verry happy, if anybody coul help me out, or even had a picture or so.

cheers
stranz