Please make sure you mount your resistors to the frame of the truck using the included screws. Drill small pilot holes, position your resistor with the 3m tape and then fasten the resistor with the screws as seen in the video below. One screw per resistor is typically plenty, but two per unit is best. The resistors get hot, please do not touch and be sure to mount securely to the metal frame.
Once you install your lights and are ready to connect the resistors, you will attach both resistors to the same ground wire. Then each resistor will connect to a single power wire. The wire can be found by following the brown wire from the bulb socket into the PIN connector and seeing which color comes out the other side.
Some examples are below, but following the guide above and in video below will result in success, regardless of color.
One Fellow F150 owner reported their 2018 XLT wire colors to be grey with orange and blue with green on driver side. Passenger side was green with orange and green with purple
Another fellow F150 owner has reported their 2019 wire colors to be blue/yellow & green/orange.