A tool and a method for replacing brake system components for automotive vehicles. The tool is designed to rotatably secure a worn or defective treadle valve side by side with a rotatably secured replacement treadle valve. The treadle valves can be rotated and locked into place to present corresponding faces to the user. The tool and method allows the user to measure the orientation or alignment of threaded fittings on the worn or defective treadle valve, remove them and then install them or their replacement fittings on the replacement treadle valve in the same general orientation or alignment as the fittings had on the worn or defective treadle valve. The tool and method ensures that when the replacement treadle valve is reinstalled on the vehicle, the threaded couplings on the ends of lengths of tubing will align with the fittings installed on the replacement treadle valve.