I just read through this entire thread... on one hand I am kind of chuckling, but on the other, I am feeling a little pain for you fellas.
Ok, so toss out all pretension, and I am going to gamble there is humility out here.
I will speculate what I think, and post what I know:
First off- this gimbal is basically just another version of all the other Chinese 2 axis gimbals out there albeit with some variations in order to fit your birds. (P2?) (Vision?)
I see that the board is Arduino, and it is standard BGC software driven... most likely one of the later versions.
The power is definitely as you have finally discovered- 3s, and you can solder a lead and route through from the main terminal as has been suggested to power the board- a small red female JST connector and it is removable for servicing.
Now- these gimbals are usually "tuned" to the camera they are to hold: placing a piece of garlic or lemon will not get the balance right as they are set up per weight- so whatever camera is supposed to go on there (DJI I imagine) is the weight to work with- otherwise some adjustments on the gimbal software will need to be performed.
The pitch wire is a 2 wire- and on the Naza it should be connected to F1- the top wire on F1 is signal (moves the gimbal) the middle wire is voltage (5V) and the bottom wire is ground. On my radio (stock with a Phantom v1.1.1 and NAza V2 like yours) I have smooth movement per the slider on the back of the radio with the signal and ground connected. I cut the middle wire out.
Now for the bad news (if that above wasn't scaring you, then this ain't so tough maybe?)
There is a port on the board to connect to a computer- basically, and this is my best guess, you need to first contact the vendor and find out which version of SimpleBGC firmware that thing is running. Then you need to download the gui and learn all you can about adjusting this booger here:
http://www.basecamelectronics.com/downloads/
All firmware is on that page- there are a ton of youtube vids on pitch control for the, and here is where pride had better be pushed down deep, something called a "goodluckbuy" gimbal- they retail for about $80 and are balanced for gopro hero 2 or 3... but the platform can be tweaked to any weight once you understand the gui and software.
If you fellas are autodiacts like me- then you will wade through this and mod up something cool no doubt- if you are not, then you had better just shoot for a return.
There is one other option and possibility- I am totally wrong about everything I posted. I am not holding my breath though... I have spent a minute on this.
Best of luck.