i'm in the same boat as you - been looking around for some ideas and dims - this is what I have found so far:

http://www.xoutpost.com/bsws-mobile-e...b-project.html

http://www.xoutpost.com/bsws-mobile-e...ight=enclosure

http://www.janixworld.com/x5/Stereo/

i'm not the greatest woodworker, but i really want to come up with a more affordable solution than buying the jl or the bsw...

let me know if you end up making one - maybe post some pics and dims please...