Obviously, this is the bottom of the car. You can see the battery connection (little red box) and the wiring to the motor and switches.
This was the first "complete" car. I replaced the crappy looking homemade wheels and stablized the motor/gear box mounting with a plate rather than brackets.
This was the first modified gearing. You can see the slight torque on the red gear. It ran smoothly enough and I estimated the ratio at around 25-30:1 although I didn't count all the teeth.