The grommet behind the glove box is effin huge. Pull it out a decent amount and take a razor blade to it. I ran 2gauge wire through it as well as 8 gauge and had room to spare...
You can easily run it along the plastic on the bottom of the doors...OR depending on your amps size....mount it under the seat. I have a kicker kx250.1 and a nine.1 under my seats, and the rear passangers still have enough room for their feet to sit comfy like.
I think you have about 15" in length, ~3" in height, and 12" in width (front to back)
If someone decides to break into your car and see's the sub, logically the amp would be in the trunk as well or mounted to the box, but under the seat its a bit more difficult to get to, little bit of piece of mind.
TSUNAMI, ive always wanted to do something fancy with my amps and sub boxes but I need the cargo space...your setup looks good, id love to pop the hatch and have nicely displayed amps...