Use the locking nuts to secure the end link to the car. Use the plain nuts to secure the bar to the end link. Do not use anything on the nuts, just put them on dry and torque them down. Do all this with the car sitting on the ground. Pay attention to the bar bushings to get them oriented correctly. My bushings had small green dots and I matched the position of the green dots to the position of the dots on the OE bushings that had white dots.