is it possible to install aftermarket navi inside the navigation cover...the place where navi goes in when you get it at the dealer

 

Yes, I'm using the Kenwood kna-g510 nav box and Kenwood lz-702w monitor for my touchscreen GPS, cost me a little over $700 shipped:

https://my350z.com/forum/audio-and-video/270820-look-what-ups-brought-part-2-a.html

I've since moved the nav antenna under the plastic for the rear tower bar so it's a completely stealth install.

 

cool thank you very much...i hope there isnt any wires sticking out or hanging next to the console..

 

Nope, the wire you see in the pic is for my radar detector, been lazy about getting a hardwire kit for it. So you will have 0 wires visible