57-58 Finned Drums with Numbers by Lug Holes

[Bob B.]

Hi all,

I was sandblasting and repainting a couple of the 57-58 style finned drums and I noticed numbers written next to all five lug holes on both. The numbers are in red, written below each lug hole, and are in the upper 200 to lower 300 range. The numbers are on the metal, so they are either original prior to dip painting or someone previously sandblasted them, put the numbers on, and then repainted them.

So, any idea if these numbers are factory or not, and, either way, what the significance is?

Thanks,

Bob