rear view camera? 2006 h3

I am installing a rearview camera I purchased on ebay (that i haven't recieved yet)to my 2006 H3.  My question is about wiring the camera so it will power up when I am in reverse.  

I know that the reverse light is "light green" in color and can be easily accessed on the driver side kicker and also in the tail lights.  The instructions for the install from the ebay site is as follows:

Easy to Install. It is easy to install the camera.  Just plug RCA Video Jack onto your car monitor, and connect 12volt (Red wire) and Ground (Black) to the power. That's it. Do-it-Yourself.

My understanding from the instructions is that the 12volt red wire and the ground black wire both splice into the light green reverse light wire. My first question is doesn't the ground wire just connect to a bolt on the frame?

My second question is about the head unit I am using with the camera.  It is an Pioneer avh p5700.  Below is part of the install instructions for use with a rearview camera.  The question is do I clamp the violet/white extension lead to the light green wire?

My last question is if I want the choice of having the rearview camera powered on at all times (while the car is running) and not just when it's in reverse, what would I connect the red 12volt wire to in order to accomplish this.

To recap my questions:

1.  What do I connect the black ground wire from the camera to?

2.  What wire do I clamp the extension lead from the head unit to?

3.  If I want to view the rear view cam while driving and not just in reverse, how do I go about wiring it in order to accomplish it?

Thanks in advance for anybody's help!