I was going to leave the factory airbox in the engine bay, as I know they have nothing wrong with the amount of flow they can handle.
Sway bars is a good one for sure.
Exhaust is a tricky one. I want something quiet and preferably legal or close to in terms of CAT location.
Is it possible (without having a Stagea in front of me - damn it, to put the CAT in the dump or close to?