What's up everyone, my friend is looking into getting a 04 GTO I was just wondering what the best option on exhaust was. I'm sorry if this is a broad question but I am a Ford guy

hahaha (I have a 03 Lightning) I am not here to start any problems, and I'm not one of "those guys" I'm just here to try and help him out. He is looking to make this thing a beast. Thanks for any input
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