1968 Camaro jack

[L78M22Rag]

I’ve been scratching my head about this for years. Can someone explain what this round metal ball is for? It was stored with the jack for my 1968 Camaro. It’s a hollow metal ball that has a round hole on one side and the opposite side is flattened with a square hole. Is it simply for jack and tire storage?

Perhaps it’s not even associated with the jack, but it’s the same colour?

Also, where does this other little bracket fit? I haven’t seen one of these either, but it looks like it’s meant for storage of the jack in the trunk.