stock mounting depth of 3rd gen??

[MillerTimeX17]

well, looks like im gonna have to get rid of my subwoofer box that is behind my 3rd row in order to start hauling around baby strollers .

so here is my question: what is the mounting depth of the stock subwoofer box in a 3rd gen? and also, does anyone know the volume of the box?

i am going to get rid of my 12" alpine type r and fab up a way to fit a 10" in the stock location. it will be run off an alpine mrp-500.

here is the old setup:

 

[MillerTimeX17]

P.S.- this is what i want to put in the stock box:

http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=17706