Yeah, I know. But sometimes junk and stowage was just piled up and the gunner just stood on whatever was there. In some vehicles a bum strap was provided, like a tiny hammock suspended from rither side of the gun-ring, as a seat for the gunner. In some cases the gunner just sat, or balanced, on the edge of the gun ring with his feet forward.
In any case, the hard cooler is strong enough to stand on.
Final pics to follow soon.