Looks like something you'd see at a pro garden center or nursery. 
I needed to move some rock for a project.  Hate the sound of rock clanging when thrown in a metal bucket.  Built a wooden box for my grapple on the Kubota so I can just lay the wood box in the grapple when needed which eliminates the noise and avoids having to change SSQA implements. 
Here's a picture.  When I need to mix concrete, the bed of my truck is about the right height to load it into the mixer without lifting the bag.  After mixing, I dump it out the other side into a plastic mixing tub inside the wooden insert on my grapple.  
While my grapple would also work for carrying chainsaws, etc., if I were to use it on my Power Trac,  my intentions are to fabricate a different style of log puller for the Power Trac.  So I'm trying to figure out how to carry my chainsaw, etc, on the body of the Power Trac.   
But as a general tractor carryall, I like what you've done, Runner.