WARNING: This page is about a different car, the 2007 Chevrolet Monte Carlo and 2007 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
Install the NEW catalytic converter pipe hangers (1), if necessary.
Fig 1: View Of Catalytic Converter Hangers
Courtesy of GENERAL MOTORS CORP.
Remove the support from the exhaust system, if necessary.