I was looking for some storage ideas on how to prevent stuff from rolling around deep in the bed. I ended up cutting some 2x4s and dropped in the slot making a divider. Now I can just put some baskets in the back for groceries and such.I made my own because there just didn't seem to be a lot of options out there that were specific to what I needed. There are plenty of ways to tie it to the bed.
Yes I realized that it was sitting up and did what you said. It sits flat now. Love the paint job on yours. The bungee cords is a great idea.I did the wood separator board thing too, you are right- it's great for groceries or small loads.
Note: if you round off the bottom corners it will sit flatter.
I put some D-rings on it for bungees.