Alright i'm planning on installing the D3 in my 07 civic. I'm gonna purchase the center dash piece that comes with the navigation model. i'm not exactly sure how this whole bracket and mounting stuff works so i have a few questions. First heres a little pic

alright, where would i obtain those brackets? are those already on my current OEM radio somewhere behind the dash? will they come with the new OEM dash peice from the dealer? or will they come with the D3?
Also, once i do have the brackets attached to the avic, what do the brackets themselves mount on too? are the brackets put onto the dash piece allowing the entire unit to be basically held in by the dash piece?
Thanks for the help everyone, i'm a complete newb at this sutff and i want the satisfaction of doing an install by myself.