ok well i'm starting to plan out my dual 12" sub box and i wanted to double check to make sure i have it right...

i figure i need 2.5ft^3 internal volume ...

1" MDF:
(4) 32 1/8 x 14 1/8 pieces (should i have one piece cut larger to fill the opening behind my backseat or just build the box and then have another piece cut fill opening w/ a cutout for the box ?)
(2) 14 1/8 x 14 1/8 pieces

now this should give me the 2.5 ft ^3, right?

will home depot cut out the openings for my subs too?? i have no way of doing it myself...oh, and does anyone no how big the openings should be???

then once i have assembled the box (with silicone to seal it - thanks audiolife) then i need to spray the inside with dynamat and then carpet the outside and install the subs..

thanks for all the help,