When ever I need to carry something around I take my backseat out and put it in there. I have 2 amps under the backseat so if I was carrying something big around it wouldn't sit level and roll around. So I decided it I would fix it so it was level and my amps could still get air to them. I chose expanded metal so since it wouldn't muffle my music as much as wood would. I got the idea as a offspring from a bunch of the ones I have seen up here.
2- 2x6's 34" long each
1- 34x34" piece of expandable metal
and a few screws and washers.