PStov98TJ
TJ Enthusiast
Diff covers are an oft debated topic. I can tell you from personal experience that the basic rule is very simple. If you hit the diff area hard enough to need a bulletproof cover, you will have destroyed something else on the axle long before you need the cover.
Aside from what has already been said about using an OEM or Barnett diff cover, this was my other thought. Save your money and sleeve the axle tubes and/or get a truss. Save room, especially on the front diff cover. Big ones don't play nice with the track bar and sometimes like to get a little too close to the tie rod as well.