Newbie first build


I have experience working with UAVs for the last 8 years but I always use electric brushless motors.
Now, I want to build a rover converting a 49cc gasoline quad using a pixhawk and Ardurover.
The main issue is how to control PWM throttle from the motor. For steering, Im going to design an adapter to the handlebar attached to a servo, as a normal remote control car.
Any suggestions about drivers, hardware,…?

Thanks in advance