Garmin Nuvi 660 GPS Receiver "hardwire car stereo" Questions

hardwire my Garmin Nuvi 660 in to the car stereo. I would preferably have the Nuvi interrupt the stereo's music for navigation and handsfree mobile phone calls. Does anyone have the Nuvi output wiring

...hardwire the information is below. 1994 Nissan Pathfinder Car Stereo Radio Wiring Diagram Car Radio Constant 12V+ Wire: Red/Black Car Radio Switched 12V+ Wire: Blue Car Radio Ground Wire: Chassis Car ...