ok heres a picture of the box i built. i made it to fit perfectly in the space, it cannot move forward, back, or side to side. love it. may not look the best, but im more for functionality rather than looks.
just a simple box, two compartments inside to keep thigns seperate, simple handle on top. on the inside i glued on strips to keep the lid from moving around as well. and put rubber strips to keep it from making noise when it shakes or vibrates from bumps in the road.