I cannot remove screws on Y rail to attach stepper motor

Machines (Elite Series)
1

These screws: Imgur: The magic of the Internet

They just spin forever. There appears to be a nut inside the plastic piece with the engraving on it, which affixes the drag chain holder to the rail, and that nut is spinning freely. What am I doing wrong?

2

Yes, you need to take the rail mount off. Their also stop nuts there