Do not waste your time on it...
I have made a new tanker also (KC-46), but I can't reassign the refueling point positions.
Seems like this points are hard coded for the both working World ID's. And it's animation parameters - Up/Down, Left/Right also limited by the game code.
There is small chance what KC-10A World Id's is working, as it still persist in wstype scripts, but again, it has only one refueling point for the flying boom...