I have an 06 MC with the HK stereo; I just bought the kit for the aux jack to use with my iPod. I plugged the cable in the back of the unit and it works just fine. I routed the cable down and made the end pop out through a slot on the little door below the toggle switches and behind the cup holders, that way I can just leave my iPod down in the cubby. I think I like this better than keeping it in the glove box.

Has anyone else down it this way? Any problems?

 

My aux jack is in the cubby too. Judging from the forum, it is one of the most popular locations to install it.

I put mine down low because I wanted it to be easily visible:

The thing in the slots is an LED that is tied to the footwell lights.

 

I like that... I went ahead and mounted the plate and jack there. Looks better than hanging down through the slot!