Hi, I just bought an 06 GT and I already have an idea of what I want to do with it. First up is exhaust. I want to make it louder, but I want it to still be legal. I was thinking of getting some sort of catback exhaust and then installing BBK shorty headers. I read that shorty headers bolt right up onto stock cats, but that was for a completely different car. If I install BBK shorties on my 06 4.6 GT, will they bolt onto the oem cats? If so, would I also still be able to install a catback exhaust?