I just bought a 2007 G35, which came with the NAV system. From my previous vehicle, I am looking to install a Double Din In-Dash. Because I live in Hawaii, the stock NAV doesn't have my area in its system FML. I searched around and found that I would need an aftermarket one installed. What I want, is to have an aftermarket GPS system installed to my stock screen while being able to use my after-market Double Din. If not, the stock screen would just become useless. I am stuck and any feedback would be jeezy

 

Just make your stock nav screen a dvd/entertainment player and use your aftermarket dd the nav and other things. Maybe you can buy a disc for your stock nav with an update for hawaii stuff.

 

If the NAV has an audio/video output, then tap into the AV input for the Stock NAV.

 

^ The 07 coupe (which, based on the OP's mentioned of a DD kit) doesn't have an AV input for the stock nav.

back to the OP
I just left Hawaii, so I feel your pain. The stock screen won't be entirely useless, since you still can monitor maintenance and gas mileage info, but yeah, basically useless.

To get navigation on the stock screen, you've got a few options:
A) + http://www.avelectronic.com/NavigationVideo%20Camera%20Interface.htmlThis would probably be the most factory-like install, since it would be independent of the radio, and you wouldn't have to shop for your DD radio based on navigation functionality. I'm not sure how expensive the avelectronic adapter is, but between the two devices, somewhere around $600 would be about right.

B) Double Din Navi + avelectronic adapter
Most DD navis have a video output, so you'd be able to display the same screen to the more visible popup screen. Since you're planning a DD conversion anyway, this is probably the best way to re-use the factory nav. You'd be tied to DD radios that include navigation (which still gives you a lot of options) but most of the best DD radios have navigation anyway, so this is still a good option, and lets you use the touchscreen on the aftermarket DD radio/navi instead of the remote with the GVN53.

C) Any aftermarket Garmin + a suction cup mount
Pop the navi up and use an windshield mount to stick it in the stock position. It's cheap, it works, and it's easy.

D) DD Navi + ignoring stock system
Less expensive than using the avelectronic adapter, but doesn't put the screen where you can see it. You can always add the avelectronic adapter later if you must have it on the popup screen.

 

So basically, it's just an av electronic adapter I should be looking for. The Garmin GVN53 is tempting and does sound nice thou. Haha thanks for the options, got lots to think about now.

 

Well, it's an adapter made by AVelectronic.

Too bad you weren't asking this a year ago, I'd have been there on Oahu to help you out.

 

Thank you