If you're considering an ARB Safari Snorkel for your 2.5L TJ, and you have AC, please take note of this thread.
The part # is the same for the 4.0L as the 2.5L. No worries, you're getting what is available for the 4 cylinder.
Follow the instructions provided from ARB, except for the following:
The stock routing of the air tube from the snorkel to the airbox will not work without some modification. The tubing will rub against the motor and the belt. You can make it work, you only need to do the following:
1. Cut the new inlet tube you attached to your airbox down 1.5", while lessening the angle it comes away from the airbox. Be sure to leave enough at the bottom of the inlet for the tubing to adequatly engage with the hose clamp.
2. Raise the airbox 1". I bought longer bolts (1/4 20, 2") with 1" worth of washers (use less washers and another nut to keep them from coming off when you remove the airbox in the future). This will allow you to better clear the belt.
3. Bring the tubing up from the fender, between the high pressure AC lines and the battery. Don't try to bring it directly to the airbox parallel to the lines.
4. You'll need to clamp down the tubing to the airbox with a long tie-wrap, to prevent it from bowing out towards the motor and belt. I cut two holes in the airbox, and used one of the really long tie-wraps which come with the snorkel.
See a few posts down for pics. I didn't get any prior to the modifications, sorry.