Android Full integration

I'm starting a project to make android fully integrated into the MFD.
I don't know if anyone has done it here so please let me know if someone has.
Reason why I'm doing this is because I always like the factory look, and I don't want to install aftermarket deck.

Here is my plan so far.

1. Integrate Tronsmart mk908 mini-pc (running quad core A9) under my front seat. ($100)
2. Navtool (or similar) to get the video into the MFD (I have stock navigation gen4) ($210)
3. HDMI-Composite RCA converter. ($40)
4. Get 12v from battery (use SPST relay since I think it's gonna be using like 6~7A total, which will overload my 7.5A ACC already running on the car)
4.1 I'm trying to decide whether to use ACC from center console or from Nav to trigger the SPST. Suggestion from people will be appreciated.
5. Install Wifi Hotspot running on 5v somewhere in the car where it'll get the WiMax signal. (Already got both Karma and FreedomPop.)
6. Use 12v to 5v Converter, then make 3-4port USB hub to power Tronsmart, Wifi Hotspot

It's pretty simple concept, but I'll try to make a good Box-case to install all these out of 3D printer so it'll look like I'm actually installing a factory product. I might throw in some small fan if heat becomes issue, but hopefully natural ventilation will be good enough as I hate having moving parts.
I'm looking at spending 2013 summer to slowly acquire product and design the box.
If others are interested, I can probably give you the data for the Case to get it printed, or I can print it and send it to you.

Quick question if someone has answer.
How much trouble is it to upgrade from 05 to newer MFD with higher res?
If I'm gonna be doing all this, I was thinking about upgrading MFD too if all I have to do is change the screen and the Nav under the seat. Do I have to replace the wirings and something else also may be??
Thanks

I just got my prius and joined the forum so looking forward to meeting you guys here.

Nori