Excellent questions. I'll post more pictures when I get home from work.

The semi circle at the top of the box is because I originally intended to use the stock cover thing, but it turned out to get enough airspace I had to make the box extend out too far for that. I was going to change the shape once I decided to change how I was going to do it, but I'd already put so much time in I said F#%kit.

Same reason basically for extending out the bottom part. The magnet on that W7 is massive, so to get enough airspace with the sub mounted in there I had to use as much below the deck of the trunk as I could.

Recommended airspace with a sealed box is 0.875 cu ft, so I was shooting for 1.0 cu ft just to be safe. I couldn't quite get a cubic foot of packing peanuts in it though once I was done, so I'm slightly under 1.0, but I think still above 0.875.