I would exercise caution as you pursue this. The regulatory climate in many states has soured for modifications to daily driver-type vehicles. When you begin to modify systems like braking, steering, throttle operation, etc. you can run into a buzz saw of liability. There are firms that build custom vehicles like this but they come dearly because of the regulation. I would start your journey on this particular basket of modifications at your local DMV and branch out from there to make certain you are not unknowingly in violation of some vehicle code in your state.