We used the manual knob to operate the headlamp rotation several times before we were happy with the operation. Removing the covers will allow access to the wires and cables should you need to do any tweaking to get the right fit. Once again, this is the most important step of the install. Make sure you're happy with the operation before you put power to the system. Our fingers were getting a little numb by the time we were finished, but seeing the lights for the first time makes the effort well worth it.