Have a bit of a mystery going here. I noticed a marking on the side of a Bally ST in a FB for sale ad that looked a lot like the marking that is on mine, which I had assumed was some sort of graffiti or something an op had put on it. We found another ST here in Houston has the same type of mark, and when I looked on IPDB, there it was again. The mark is EST followed by a 5 digit number, so probably (Something)StarTrek followed by the serial number, since there were 16k units made (see pics).

Anyone have any info on what and why these are?

Image from iOS (resized).jpg

from ipdb (1) (resized).JPG

superweird (1) (resized).JPG

wonder what the E is for?

and why do some not have it?

and why put that in plain view on the side of the cab?

no mark (resized).jpg