Remember, any alterations to a ride-on car will void the warranty. Also be sure your kid can handle the extra speed!
Kids 12V Jeep: https://amzn.to/3PaR07Z
300W buck converter: https://amzn.to/3JH0uqr
Buck converter enclosure STL file for 3D printing: https://www.thingiverse.com/thing:5452606
Milwaukee battery adapter: https://amzn.to/3BPHy6G
Butt splice heat shrink: https://amzn.to/3bCUnH5
Connectors: https://amzn.to/3A7HjCJ
Heat gun nozzle set (fits M18 heat gun): https://amzn.to/3bCUxhF