Depends on what bumper you're using, and if you're just going for the looks or actually want functional.
Functionally, it's doable, but there's not a lot of room. Definitely would need to custom build, no one sells a true quad exhaust kit for our models.
As for aesthetics, the stock bumper really only has the two outlet "bump-outs" for the stock twin exhaust. I've seen people chop theirs up and fabricate new surrounds for the wider holes, but I've only seen one that looked decent. Better choice would be to switch to a GT500/CS rear bumper. Also has only two outlets, but the areas were the outlets are is an unpainted blacked-out space that can easily be cut and still look good. You could put dual-tip ends on each pipe, that would give the quad-exhaust look. Won't do any performance/sound difference, but I'd say it's an okay mod if you don't use cheap-arse exhaust tips.
Performance-wise, I'm not sure there's anything to be gained with these engines, at least not in the lower 90% of builds. Maybe with a monster of an engine build.