2003 Nissan 350Z audio upgrade?

Not to take away from the12volt.com, but check out www.my350z.com.  Their forums have a few people who have done the upgrade from the Bose system and the non-Bose system.  As far as the factory's anti-theft security system, the 350Z radio itself doesn't have any protection built-in, but it does have the wires for the 3rd display integrated into it.  If you remove the factory radio (without grounding that 3rd display wire), then the 3rd display won't function and the customer won't be able to see his gas milage/tire pressure/miles traveled on this tank/etc.  The forums at www.my350z.com can tell you which wire it is (since they are different depending on the Bose vs. Non-Bose models).  Good luck.  Keep me updated on the project.  My system in my 350Z may be next.