This one has the "bumper numbers" on the sides of the rear stabilizing jacks.
This one has them on the side of the boom.
The one w/the box you are talking about is most likely a British version. Below is a Brit one w/ the black rectangle and white letter/number combo "bumper numbers" on the upper left of the body, next to the window.
Gino P. Quintiliani - Field Artillery - The KING of BATTLE!!!
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