Greg, just to let you know, I took a 2x4 about 1and a half foot long and ripped it down the middle lengthwise. I then used those two long, square peices to screw the two other peices together. Kinda like a backing reinforcement of the jount between the two plywood peices (shelf deck and rising peice) so that I could anchor them together. Anyway, I found that it made it exceptionally more sturdy than butting the two peices of plywood together alone and gave the screws something extra to bite into. I suppose you could use metal brackets here but I just had some extra wood from my deck lying arround the garage. Also, If I had to do it all over again, I would have made the bottom unit and then put the vinel over it as if it were one peice and not two. I had to screw through the front of the vinel to connect the rising part to the shelf deck (not visible though). For the speaker box, I just used 3 peices of 2x4 blocks and slapped on the plywood face with the speaker holes cut out. I then put some vinel over it and just screwed it on top of the shelf from underneith. It's pretty sturdy. If you go with the plan from Foster, which I did and it fit perfectly, you might want to consider that it does not leave that much room for the speakers. You may want to make you storage doors a little smaller.

Anyway, I am very happy with the result and although it was time consumming, it was not that difficult.