I have an interesting thought on where and why the top is missing.
In 1932, before robbing the jewelry store, he remembered that damn T206 in his pocket in which he wrote the address to the store on the top white border. Not wanting that evidence on him, he cleanly cut it off........the store owner found the card on the ground outside after the robbery.
He instantly recognized the mug on the card (albeit, a younger version!) and Mr. Downs was in effect "Down for the Count!"
This could have happened.....?!?!?!?
In my dreams!
Peace, Mike