Up for sale is both the inner panels and the outer skin for the rocker panels on a four door 1997 - 2003 Pontiac Grand Prix and, I think should also fit: 2000 - 2005 Chevy Impala & Lumina. BRAND NEW, Bought to fix my car and ended up going a different route.
Part numbers for the Inner Rocker Panels are:
12458992 (Right Hand Side)
12458991 (Left Hand Side)
The outer rocker panels were from ebay and are for a 1997 - 2003 Grand Prix, I can't guarantee they will work for the chevy models but they should.
Asking $300 for everything, from what I gather you can't find the inner rocker panels anymore. Pick up only, rather not try to ship these, located in PA 19465
PIC: http://imgur.com/sbTlP3g
