Remember those kick-ass drivable Mario Karts unveiled at the L.A. Auto Show earlier this year? Did you know they started out as glorified golf carts.

Well, sort of.

In this video, West Coast Customs founder Ryan Friedlinghaus explains how they turned those electronic GEM cars into monster, driveable, minutely-detailed Mario Karts. They started by essentially throwing out everything but the motor and battery and building everything from scratch.

The end result is spectacular.