A clarification on an earlier ruling found here:
Would laser engraving motor backings/casings be legal?
According to the game manual:
Our team would like to laser engrave the green plastic backs found on Vex 2-Wire 393 Motors. This would allow us to put the port number on the back of a motor, clearly visible. Since laser engraving works a fraction of the way into the casing, it would not rub off after multiple seasons of use.
This modification would be completely non-functional and not match affecting, only for identification purposes. Given the thread at the top of this post, it seems that this would be the same ruling since the process has the same effect. However, it isn’t explicitly stated in the manual, it seemed like a good idea to check officially beforehand.