What kind of tow hooks did you get? The XJ unit body requires reinforcement before you can mount a tow hook anywhere.
The factory front tow hook package has a bumper bracket welded to the tow hook bracket. You have to remove the bumper, replace the bumper bracket with the tow hook bracket, install the cross member reinforcement(which replaces the 2 nut clips for the bumper mount with a bracket), then reinstall the bumper on the new brackets.
Most of the aftermarket brackets require at least as much work. (some of them require you to remove the steering box bolts)
In the rear, the factory bracket bolts through the frame rail to a nut strip. The nut strip has to be installed through a hole that can only be accessed by removing the rear bumper.
If you have a hook bracket that can be installed without removing the bumper, chances are it doesn't have the bracing to safely use the hook to really pull on the Jeep.