A portable actuator assembly for remotely operating the control components on a circuit breaker which self-aligns by engaging a recessed area of the circuit breaker. The portable actuator assembly is easily and accurately aligned with the control components on the circuit breaker by an alignment fixture that engages the recessed area of the circuit breaker. The alignment fixture is moveable along one axis that lies perpendicular to the face of the circuit breaker in order to compensate for variations between the plane of the face of the circuit breaker and the plane of the sheet metal enclosure surrounding the circuit breaker. The alignment fixture is forced toward the face of the breaker by spring action to ensure it remains in constant contact with the circuit breaker. Strong magnets may hold the portable actuator assembly against the circuit breaker by attaching to the sheet metal enclosure surrounding the circuit breaker.