GL did not remove the data plates. The turning in unit did. As mentioned all the VIN/USA numbers are on the turn in paperwork and GL just copies the data. The turning in unit turned in the trailer with the VIN number that they wanted to get rid of, for whatever reason. Also when the GL folks type in the NSN information on the turned in units the specs pop up on the screen. That is why GL wants you to verify the VIN data before they issue the SF paperwork, so you catch what they did not bother to check.
GL field folks are clerks not hands on mechanical people. I doubt very much that they have many if any tools at all. Remember all the items GL gets have come through DRMO to GL.
emmado22 is right. Anyone that has spent a few years in the military knows the data plate game.