My first response is to say no...after looking at it and the measurements, I still say no. BUT! I am wrong every now and again =P I'm not sure of the dimensions of the stock sub box, but having taken it out and seeing what room you have to work with in its place and all that jazz, I say that the body metal doesn't leave much room in a rectangle config.
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'05 4Runner V6 Limited in Natural White with Stone Gray leather. Big Features: X-REAS, JBL 6 CD w/ 10 speaker system and Powered Moonroof.
'06 Chevy Express extended cargo van with a Duramax diesel & rebuilt HD/Towing trans. http://meerkatsound.com/