Stock mj/xj 96- are one molded piece of plastic.
Dash has to come out to fix the crack but its not that big of a chore.
First remove the dash bezel- two screws above the inst panel, the the rest are just clips.
Then the lower dash cover- 4 or 5 screws across the top.
Then unplug snd remove your inst cluster- be careful with the speedo cable (I found it helpful to get a set of pliers and a dmall towel to LIGHTLY pinch it and carefully move the cable shaft out)
Then remove whatever else is wired up- ac controls, stereo, clock etc
Next youll need to remove the defrost cover at the top- a couple screws
Under the cover there are three mounting brackets riveted to the dash screwed into the firewall. The windshield makes it difficilt to get to them bur a 3" phillips works great.
Last, there are 15mm bolts under the dash behind where the lower cover was- one on each kick panel. I found it easier to just loosen them rather than removing them
The dash mounts are slotted and it has to be pulled forward and rotated around the bolts.
Once its loose pull it up and over the steering wheel and out the pass door.
Not terribly difficult but help to have a second srt of hands.