CAI? or K&N?

K@N panel filter in the stock box. There are 3/4 nuts inside the fenderwell that you need to remove to take the silencer off. The rubber mounts should be threaded into the engine bay and you can retain your stock air box.
 
I have one of each and cant tell a difference.

I like the simplicity of the panel filter in the stock air box. whatever works for ya though (totally a personal thing).

Good luck.