G1 Optimus Prime Hand Storage

I recently got a G1 Optimus Prime reissue. My only problem with it is that if you put his hands into the cab of his chest in Truck mode, they just sort of rattle around.

So I made this piece that his hands can snap into, and that will fit into the cab of his truck mode, keeping everything secure.

In robot mode you can either leave the piece flat inside his chest or flip it up to make his chest seem less transparent.