I made light bars for my rc car which once was a "Vaterra Twin Hammers".
There is one for the front and one for the back. The one in the front is attached with screws to the frame, on the back there are holes to use cable ties.
It is designed so that the small NeoPixel boards fit inside (5 in the front; 5 in the back).
You can get them from Adafruit or china:
Together with a microcontroller you can get nice effects.
"Front" and "Lense" are required 10 times each and "Lense" should be transparent. It works without "Lense" but then you can't get it watertight.
FreeCAD file is included.