tips for repairing dent in door

Getting the metal hot and hammering "on" dolly will stretch the metal further and cause it to rise. Heat the circumference of the dent cherry hot? First, as the panel heats it will swell. No telling where that will end up after it cools. Might have a 4ftx 3ft warped mess to fix after that. In 30+ years have never seen anything like that.