Originally Posted by InspGadgt

He means the control arm that is on the servo. That is the arm that swings when you turn the steering. Take the servo control arm off of the servo, turn on the radio, turn on the car, reset your steering trim to 0, then put the servo control arm back on the servo so that the wheels are as close to centered as possible. Then you can use the trim to get the wheels the rest of the way to center.