Additional parts required:
4 - 2x10mm axle drive pins per light bar
4- M3x6-10mm flathead screws for light buckets
Suitable LEDs or strips
Insulated stranded wire, I prefer 22ga silicone jacketed
1.8mm (for light bars) and 2mm (for rails) drills to clean up the holes for the drive pins
Whatever filament or resin you want to use

Fairly easy to print, 2 out of 10 difficulty. Best printed with the flattest side of each part on the build plate. No supports needed as long as your slicer settings will avoid printed parts (combing off and a couple tenths z-hop in Cura). Infill is up to you. If you spend a lot of time on your roof, maybe 999 bottom layers is the best bet.

It's best to drill out all small holes to 1.8-2.0mm, depending on the exact dimensions of your axle drive pins to ensure a snug fit. Ideally, the holes in the light bars should be slightly tighter, so the pins stay in the bar when removed. Also, the extra holes make a great place to carry spare drive pins if your insanely overpowered truck is prone to snapping them.

The included light bars use 5mm wide LED strips, which I recommend bedding in UV epoxy to keep them dry. The channel on the end will guide the wires to the lower face of the bar, then through a hole drilled in the roof. Mine are hot glued to the underside of the roof to behind the cockpit, where they can go down to the light controller mounted near the receiver.