Grille (roush or Saleen or boss) GT500 spoiler, tint, lowering springs. I'm only naming these because they are the popular ones... But there are more choices. CS lower fascia plus chin spoiler, boss/gt500 rear fascia, also roush rear fascia. This is a list of things I would do
Now there are also stripes, louvers, scoops, splitters, lights... What direction do you wanna go?