Elite Foreman stepper motor installation

Just received my Foreman and attempting to install the stepper motors. The back of the left Y rail has 4 mounting bolts (2 black and 2 silver) installed that need to be removed so the motor can be installed. The black ones slide out easy enough after removing the nuts, but the silver bolts which are on the outside of the left Y rail don’t budge nor do they unthread., What am I missing?

2 more nuts behind the drag chain bracket

Take the drag chain bracket off, and then there are two more locking nuts.