I had a custom chassis-mount light kit built for me by Alpat Tugay via eBay. The whole rig is designed as a self-contained modular layer that fits onto the chassis without any tools or parts modifications. I wanted to be able to easily install the kit for occasional night runs, but leave it off and out of the way for daytime running.
I wanted minimal modifications to the body and to not have the bezels sticking out from the body at funky angles. So the front lights are attached to a stratocore bracket which fits over the body post sockets on the bumper mount. The lights will shine through whatever is placed in front of them, whether holes or clear plastic, and I can easily make new brackets for different body shapes.
The amber lights as side markers are very helpful get a good sense of the attitude of the car when it's moving at 40mph fifty yards away up a narrow street in the dark. The stratocore side brackets hold the lights out at the edge of the body and are mounted to the chassis with the servo screws.
The wiring winds across the chassis generally avoiding any moving parts. Sections of small drip-irrigation hose protect and guide the wires as they run between the shock assemblies. The 9v battery slots into the right side battery box, with wires out either end... it takes less than a minute to install or remove the whole rig.