How do you replace the idler pulley on 1997 Northstar V8 in Oldsmobile aurora?

To replace the idler pulley on a 1997 Oldsmobile Aurora with a Northstar V8 engine, first, disconnect the negative battery cable. Remove the serpentine belt by using a wrench on the tensioner pulley to relieve tension. Then, unbolt the old idler pulley from its mounting bracket and replace it with the new pulley, ensuring it’s securely fastened. Finally, re-install the serpentine belt and reconnect the battery cable.