Just for posterity...
I installed mine today in my '07 w/Nav.
I wanted the space in my glove box, so I mounted the XM unit inside the center console cover - between the shifter and the arm rest portion. Had to remove a switch guard, but I see no problem with what I did.
I mounted the Terk unit same location as waterman.
The antenna is on the dash (double sided tape), right side, basically lined up with the end of the right wiper arm (where it connects to the blade).
Everything works perfectly. Went for a long drive, out of town into the country, and never lost signal.
My only complaints are the length of text displayed (seems limited to ten) and you have to push the audio button to see who's playing. I think those issues may be HU issues - not necessarily the XMDirect???
I really appreciate this thread and especially Waterman for the pics and explanation.
Absolutely worth the time and $ - a no brainer.
I just realized I probable should have taken pictures. If I ever go back in (likely), I'll snap a few.
Thanks,
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