[TomH]

It doesn't have to be COTS to be used on the robot, my post was incorrect before, it is now edited. By cutting down the wire, it most likely will lose its COTS label, ex form manual:
Example 1: a team orders two robot grippers from RoboHands Corp. and receives both items. They put one in their storeroom and plan to use it later. Into the other, they drill “lightening holes” to reduce weight. The first gripper is still classified as a COTS item, but the second gripper is now a “custom part” as it has been modified.
(Page 4, Section 8, under COTS)
It will be still considered legal, but most-likely will be considered a "custom part".

Also, I apologize for any misleading information in my first post in this topic, I was too at one point confused. I recommend that if you are still confused, you read the manual, specifically page 4 of section 8, to get a better understanding. By modifying it to say reduce the length of a cable, it may be considered "custom" because you have changed it from its original commercial form. The only things that COTS gives a specific object is that it was entirely unaltered, and if removed, looks exactly as it did when taken out of the box.