Thanks for the ideas. Luckily, The box is built so I have access under each shelf to drill the holes.
Accidentally, I never glued the top on, so that will help getting this all together.
Radio box temporarily sidelined for installation of the SteadyFast stabilizing arms for the 5er.
Hot sun, lots of steel drilling chips from drilling the 5er frame, covered with dripping oil from trying to keep the bit lubricated and not too hot. fun.
http://www.steadyfast.com/index.html