Two Wheel Fix - Mounting a top case for my KLR, cheap

I'm looking at mounting a top case for my KLR pretty soon. I bought a seahorse case (almost like pelicans only cheap), and I'm looking at my options to mount it without having to spend an arm and a leg for a mounting plate.

So what I'm looking at now is a home depot special. I have a few designs that I'm considering, but I do have some oddly specific requirements. And here is the real kicker. I want to add in 2 12v outlets, one outside the box so I can plug in my just ordered Sena SMH10, and one on the inside, possibly with a switch on each one on the outside of the box to turn each one on or off. The switch is just an idea. But with the fact that I want the box removable I need to be able to plug it in to the bike. I already have 90% of the wiring for electrics already installed, just need to run wires from the fuse box to the tail. I think I would use some type of compact marine plug or the same type of fitting that my trickle charger works on.

Here are the designs I'm looking to copy

Option 1

http://www.oldrice.com/images/boxmount3.JPG

http://www.oldrice.com/images/boxmount5.JPG

http://www.oldrice.com/images/boxmount1.JPG

Option 2

http://img694.imageshack.us/img694/9144/dsc00505mi.jpg

http://img705.imageshack.us/img705/6234/dsc00510a.jpg

http://img706.imageshack.us/img706/6508/dsc00516st.jpg

Right now I'm leaning toward option 2, its less bulky, and leaves more open space, and a flat area on the rack when the box is off. Anyone have thoughts or ideas, or better ways to mount a case? I'm really open for almost anything, as long as it doesnt cost an arm and a leg.