Thanks guys. The frame is made from 1"x10" pine and 3/4" plywood for the top. Its covered by some thin outdoor carpet I got from Home Depot. They have it on a big roll in the store that you just cut off however much you want. I got like 6'x12' for something like 30 or 40 bucks.
I have four plastic bins like you see in the picture that I have all my camping stuff packed in that fit perfectly underneath the center sections. The sides I have stuffed with all my tie-downs, axe, gloves and other random stuff. The center section is easily taken out and either layed on the bed in middle or put aside if I need to put bigger stuff in the back like my mountain bike or something.
A side benefit of this is that since I'm always carrying my dog around in the back I get to keep all my stuff under the platform where she can't chew on any of it