I've just purchased a 2011 gt500. I have a predator tuner,jlt 123 cold air intake and 2.6 pulley and idler. Not installed yet but on the work bench to go in.i guess my question to everyone is do I run tr6 plugs now? Colder thermostat? My next step with the car will be exhaust it has borla mufflers now. But need a deeper sound for me. Was going to go with off road x-pipe or should I go with high flow cats? Throttle body needed now or wait? I know some of you guys have bin down this road already so I'm looking for your knowledge. Thank you