I wanted to change out the mirror so I could have front and rear cams (one day all cars will have this) and loop recording.
This neat rearview cam has all kinds of goodies on it. so decided to buy it from amazon.


It has gps, google maps, and so much more. Blown away by what it has.
I plan on swapping out our mirror and housing somehow, keeping the garage door functions and doing away with the auto dimming and NSEW signal in top right corner.

Here are a few threads I found that may be of help.

I wont get a chance to post all steps but maybe someone can chime in like tecman to help here.

https://www.clublexus.com/forums/is-...zzing-fix.html

https://www.clublexus.com/forums/nx-...ew-mirror.html

 

I put a Gentex multi-function RV mirror in my Land Cruiser years ago. The "easy" part is the physical mounting of the mirror and housing. Since the GX is provisioned with a similar setup on the windshield, you might be able to keep some of the plastic used to hide wires and integrate the roof and the mirror.

Then you have to run all the wires....up into the roof, down the A pillar, then behind the dash and through the firewall. Painfully tedious, but not hard if you now how to take apart the interior parts to get wires behind them. It's quite a bit easier if you are just doing a full swap, and need to get power to the mirror, plus enabling functions like the garage buttons, compass, temp, etc.

Edit: I see you're in a 2014 now, so maybe the new GX mirrors are upgraded/different. I can't comment on the newer features that you may want to retain.