Here is one way.
http://www.e90post.com/forums/showthread.php?t=157728
This path exists on the M3 but is harder to get to due to the larger engine.
There is annother way going through the ECU box which puts you down buy the glove box. I haven't confirmed this however.
And a sneaky way around/through the A pillar
http://85.125.82.130/LaserIntercepto...hp?topic=656.0
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