Added holes so you can put 3mm leds in the light bar, and 5mm LEDs in the headlights.
Wires for the LEDs have channels running through the body to a cutout on the bottom
The cutout can accommodate an 18650 with spring and dome tabs glued in
A cover for the cutout which holds the battery in place and has space for a typical USB charger module (TP4056 for Lithium Ion or CN3058E for LiFePO4), and a small toggle switch,
Wheels are modified to include the caps as a single print and have 8mm holes for axels made out of 8mm pine dowel, dowel can jus be glued into the wheels