I currently have 2 12" audiobahns as well as a 800w or so amp that are going to be installed in the back of my wagon shortly. A few things I would like to know.

What gauge wiring should I run? I just planned on getting the amp wiring kit from walmart to make it easy but the question of 4 or 8 gauge I'm not too sure of.

Also, I planned on mounting them inverted. Is it alright to make the box shallow ( 4-6 inches) as long as I have enough width and length to have the right area inside the box?