Alright, I got a dimension for you.

If you build it this size, it will be very close to what they told you to use.

IF the 2 cuft was for the outside dimension and they took into consideration the wood and speaker then you can build it to this size
These are the OUTSIDE dimensions all in inches

12 inches deep
15 1/4 inches high
19 inches wide
which gives you 2.01 cuft

That same measurement, after you figure the wood gives you
INSIDE
10.5 inches deep
13 3/4 inches high
17 1/2 inches wide
gives you 1.46 cuft

Close to what I originally told you. PLUS that gives you more than enough room to mount the amp next to the box, since the amp is less that 13 inches wide.

Here is a quick picture ( if it helps)

click the link in my sig for some help...custom sub box guide or something...thats how i made mine.

That sounds great sse1990....those dimension sound like they would work well too. I'm probably going to use those dimensions. And tanks lowrider, I'm going to use that link you have for any assembly tips.