When I purchased my S4 I did not to get the pricey factory navigation system... maybe if it had a LCD display with maps I would have but the way Audi decided to provide navigation on US cars did not impress me. I'm too lazy to read paper maps and have a short term memory that lasts about 5 seconds when it comes to remembering street names so when Garmin released the StreetPilot III I couldn't resist.So far, I'm very impressed. The auto-routing has worked flawlessly, the display is crisp and easy to read even in bright light and the voice prompts are easy to understand.

The GPS comes with mounting hardware which you can affix to the dash via double sided sticky tape but after test placement I decided putting it on top of the dash wasn't for me. I'd been using the in-dash cup holder for my eMap so it seemed like a good location for the SPIII.Satellite reception is not a problem in this location.

I decided to hardwire it for power and use the navigation speaker in the drivers door for the voice prompts provided by the SPIII. Power and speaker leads exit the edge of the glove box and route up behind the GPS unit. When not in use, I simply remove the SPIII, the mount and stow the power and speaker connection in the glove box--very clean, no clutter and not visible to tempt thieves.

	The hole in the cup holder is a near-perfect fit for a 2" SCH40 PVC collar. Some sticky backed black felt (from a craft store) carefully applied and trimmed dressed it up nicely. A flush PVC plug inserted into the collar provides a mounting surface for the GPS mount. I had to trim the length of the plug for it fit flush.
	Drop the lower panel for access to hook up power and the speaker leads. To drop the lower panel remove 4 bolts (2 behind the trim covers, pry them out) and pull the panel back and down. Release the light and diagnostic connector wiring from the panel to prevent damage. Be careful! For power, I chose an unswitched source and secured my fused power lead under one of the 10mm bolts on the power bus located under the relays. Sorry, no picture... it's obvious where when you have the panel down.
	The navigation speaker. Please, no grief about the dust and scuff marks... it's all gone now. : )
	The connector for the navigation speaker is behind the kick panel in the drivers footwell. Remove the screw cover for access to the bottom screw.
	Remove both screws and then gently pry the bottom edge of the cover outward where it meets the door sill and the carpet.
	Once you release the lock tab the panel slides back and lifts out.
	With the cover removed the connector gang from hell is revealed. We're interested in the bright green connector.
	The brown and blue wires run to the speaker in the door. I cut both wires and ran wire that connects to the speaker out plug on the back of the GPS. The output plug is a sub-mini plug--one size smaller than a normal 1/8" mono plug. Radio Shack had the plug in stock (and in gold for distortion-free connections! Yea, right). I routed the speaker and power wiring along the firewall and over to the glove box.

It does slightly obstruct the A/C vents but this picture makes it look worse than it really is. If angled up, the center vent still blows air to the rear of the car. Very nice navigation unit IMO.