i have 2 boxes in mine. I mounted the amp to the back of one, which overlaps the other (the amp in almost 24" long). I made 2 boxes so i can move them around easier. i have the 3rd row down and them up against the 2nd row now. If i need to use one of the 3rd row seats i turn them sideways. if i need to use both 3rd row seats i put them behind the 3rd row. I'm on my 2nd line output converter and still not getting the sound i want. I just wish the factory deck had pre-amp outputs. then it would sound fine.
The boxes are about 1.35 cubic feet each with 3" dia x 4" deep ports I wanted to make them as big as i could without losing to much space. Next year i plan on putting in 12's or better 10's.
i can post more pics of them from different angles if anyone wants.