I have a 1998 TJ 4.0L. Instead of spending a few hundred dollars on a high flow new air filter/intake, I opted to modify my existing OEM box. Recognizing that the restriction to air flow was coming from the relatively small mouth of the OEM intake, I removed the bottom box all together. I then loosened the pipe collar, inverted the top of the air box upside down, and secured the rectangular OEM air filter into place with large zip ties. Seems to work amazingly well. Marked improvement in power. Does anyone have any experience with having done this? Any potential pitfalls?? Not planning to submerge my TJ do I don't feel water incursion will be an issue.