I know you said you'd like things higher, but just to throw out an idea, I went the other route. I seldom look at my AM/FM radio, so it went to the bottom, and the Zumo 665 went on top ... just below the speedometer in my line of sight. The MixIt2 master volume control is at top-left, and the XM satellite puck at top-right. But the BIG IMPROVEMENT was I made my dashboard so the whole assembly comes off in one piece. Photos can be seen in THIS gallery.
Wow, this is really impressive. I assume you made the enclosure yourself? Very professional looking. Can you get at your key?