I would assume it would depend solely on the TSA screener/supervisor.
I know I had to check all tools when I was doing field service. Basically if they don't know what it is, you're going to have to check it.
GNSS suitcase is no problem. Rods, points, plumb bobs - probably.
TSA has a facebook account that you can sen them a picture of what ever item you are questioning and they will let you know if you can carry it on or not.
Be sure to check the rules for batteries.