I bought a Contico plastic box for my Toyota Truck about 9 or 10 years ago. When I sold my truck I stored the tool box in the corner of the garage. Hoping that I might be able to use it again someday. (besides storing boat stuff in it) The tool box fit perfect inside the box of the truck. It stood a little higher than the sides of the truck box. It had two doors that would flip up towards the front of the truck. (not towards the center like alot of models that sat on top of truck box rail) The doors of the tool box both have key locks. The bottom of the box was shaped to fit around the wheel bump. Now I'm thinking about putting it in my T100. It won't be a exact fit like in the other truck but I guess it will work.

I did a seach under Contico and couldn't find my exact model. There was one model that fit inside the truck box and the entire top flipped up.

There is a model that might be kinda like mine. (I like mine better.) http://www.contico.com/automotive-foam-cr.htm
Model HD61FL