I think they meant small grips on the screw, not the motor. The screw shouldn't be so tight that you can't hold onto the motor by hand as you use the grip to get leverage on the tiny screw.I'm not to sure telling someone to use vice grips to grip the motor housing is sond advice not knowing how mechanically inclined said person is. There are plenty of other ways I think of that would be far safer than that on the housing
Indeed though be careful not to put any bending force on the screw or you could snap it off or damage the thread on the motor.