you can use the '1' size rear wheel hubs for the most narrow track, the only cars that use this hub are the Porsche 911 GT3 & Lancia Delta HF Integrale. the body mount you choose is the most difficult part of customizing your own body as the measurements of each one vary based on the specific body its meant to mount. it affects wheel base, ride height and motor placement so that's your biggest challenge. i put together a
combo for custom projects like this so if its in your budget, you might wanna invest in it
