That doesn't look like the Dension 500 in the eBay auction.  You may want to contact Eric @ Bumperplugs, who is a fairly prominent sponsor on some other boards.  His outfit sells the proper unit for $479.
http://www.bumperplugs.com/DensionStandard.html
Someone also posted recently about the HK unit in a 986 that would also work on a 987 and seems fairly promising, but is not yet widely available.
http://986forum.com/forums/showthread.php?t=11000&highlight=kardon
I've also contemplated the Pioneer AVIC-D3 in a 987, which Chills just installed on his 986.  I've seen this installed on a 987 and with the proper plate looks very slick/OEM.  It's fairly inexpensive for in-dash NAV and should allow for iPod integration.  Even if it doesn't, at least it's CD-RW capable.  This is the sticking point for me.  I wouldn't care about iPod integration if the CD-24 just played discs in data format.  My playlists aren't that sacred to me.
		
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06 987S- Sold 
Carrara White / Black / Black/Stone Grey Two-tone 
05 987 5-speed - Sold 
Midnight Blue Metallic / Metropol Blue / Sand Beige
06 MB SLK350- Lease escapee 
Iridium Silver Metallic / Black
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