I Need Help With Building Sub Box..

[sweefu]

Well i pretty well stuffed everything up, so i'll delete all this, please ignore the picture of the sub box.

Basically i have a 20" x 11" x 15" box with a sloped front, i will be fitting a Soundstream Rubicon 12" 600wrms DVC 4 ohm sub

The website said the sub needs an 11.2inch cut out hole for the sub, and i have a maximum of 12inches high for the sub to be mounted in the box, will this be okay?

I will post a picture in about an hour to show people what i'm doing, it will hopefully make more sense.

Thanks.