Pacileo,
I have the bose rear deck with Focal Utopia Be subs. It going to take A LOT of tunning and proper equipment to make that box sound good. I invest 7k into my system just to get the right sound and at the end of the day was it worth it...................propably not. Don't get me wrong my system sounds GREAT but not what 7k in a full sized non convertible car would sound like. Fact is that the boxster is not acustics friendly and no matter what you do you wont be 100% happy.
With that said, once you open the Bose box up make sure you have a new seal to put around the edges as the original seal wont be as tight once broken.
I attached a diagram of my car just for reference.
Oh and here are pics of my install...
http://s338.photobucket.com/albums/n430/JDeMircift/Porsche%20Stereo/
Good Luck!
James D
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http://i46.tinypic.com/2qx0rqs.jpg
2001 Boxster Artic Silver / Black Interior
-GT3 Front Bumper w/ Lip
-Side Skirts
-Gemballa Exhuast and Cats
-O.Z. Racing 18" Wheels
--18X8.5Front 18X10 Rears
-Michilen PS Tires 225/40/18 & 285/30/18
-5mm Rear Spacers
-Porsche Door Sills
-H&R Springs
-Powerflow Intake
-B&M Short Shifter
-Pioneer Avic-F90BT Navigation
-Focal Polyglass 165VR3
-Alpine PDX 5 Amp
-Bose OEM Subwoofer & Midrange
-Audio Controld DQXS (DSP)