2003 Chevy Cavalier coolant return pipe

Seems to be a s shaped pipe behind radiator that may be hard to get at to remove without removing the radiator. What steps and where can this pipe be gotten from from? Not even GM list this as far as I can see. Car had to have the starter replaced and the garage must have disturbed this pipe that was already rusty. My son nursed the car home to keep it from overheating, just hope the head and block are still okay. The S shaped metal pipe joins two rubber hoses and one comes up on the bottom of the overflow tank.