I guess it depends on what exhaust you plan on running. Challenger T/A's and AAR Cudas didn't use those shields because the mufflers were under the back seat. Most performance exhaust systems put the muffler under the back seat and just the tail pipe along side the fuel tank. If that's the case, then those shields probably aren't needed. If you are running an exhaust system with a muffler in the stock location, then YES, I would use the heat shields.