The Metra Axxess will control your source and volume buttons (as well as up/down). The button on the 9960 just takes you into the voice activation mode. I wouldn't see why you couldn't connect the Bluetooth wiring from the car in place of that button. The wiring diagram is in the service manual. There is a download link somewhere on here. Make sure you get your year, I recently found out that they changed some of the wiring from '09 ti '10.
edit: Found it:
http://www.the370z.com/nissan-370z-o...rvice-manuals/