Strange Cabinet Numbers

[Phalanx]

Hey guys!

We've been restoring an old Defender cab with Soul Edge stuck in it, when we drilled out the locks we found a Williams sticker with "44101" on it. I'm assuming that to be the machine serial #.

HOWEVER,

During our continued sanding today, we uncovered more numbers below the coin door area in the bottom-most right part of the face of the cab. Pics below, any ideas what these numbers mean?

PS - Still looking for Soul Edge cabinet art if you can help, thanks!

PICS:

http://imgur.com/a/gvSnb

Thanks again!

[gamer12]

I think that the number on the back is the serial number.
The one under the coin door I think might be something else...
I THINK

G12

[Phalanx]

I think that the number on the back is the serial number.
The one under the coin door I think might be something else...
I THINK

G12

Now the question is...what are they? I'm been slamming my head against it all weekend.