Notes to supplement Garth's post- The usual Pantera parts vendors supply a reasonably priced kit of pre-drilled bolts and a few feet of 0.032" stainless steel aircraft safety wire. Real safety wire is sometimes available at your local airport. It takes real safety-wire cutting pliers to get those nice neat twists. Be careful- safety wire is aircraft-grade and other sizes exist; for instance, safety shear wire can be broken with your bare hands and is NOT recommended for this use.
* Many early ZFs were safety wired from the factory, but they used oversized wire that discolors and looks like farmer's fence wire. U.S. Speed shops sell a 100-ft spool of 0.032" aircraft-grade-316-stainless wire, quite reasonably.
* One of the main problems stems from OEM ring gear bolts from ZF being hardened all the way through, causing the bolts and heads to be a bit brittle and very hard to drill. Aftermarket bolts are SAE gr-8 spec and are pre-drilled. I do not recommend trying to drill ZF bolts.
* A crows-foot socket on a torque wrench is most often used on ring gear bolts. It looks like a 1" long open-end-wrench adapted to a ratchet driver. Not all aftermarket ring gear bolts are the same head size so have the bolts you will be using in-hand before searching out the crows-foot socket you need, or buy a full set of sockets. A rag jammed in between the ring & pinion gear mesh will hold the parts while torquing and not mark gear teeth. No elaborate jigs needed.
* Yes- you MUST remove the ZF from a Pantera to do all this! It weighs 155 U.S. pounds; act accordingly. Mangustas can be done in place. The side-plate bolts, once torqued down add a calculated pre-load to the ring & pinion gears. Using non-stock ZF side gaskets or changing the side-shaft shimming during seal or bearing replacement, will change this preload. Upon assembly this may cause differential-howl, either when accelerating or during slow-down- or both. Then you get to pull the box again and redo the job. Real ZF gaskets are available from Pantera vendors. I personally do not trust E-Bay gaskets.
* GT-40 crew chief Carroll Smith says to cut the extra lengths of twisted wire ends off your safety-wired parts and pick up the scraps. Those pieces have been known to puncture tires and people, and they last forever! Bend the remaining twisted ends down out of range of your fingers as they are VERY sharp and will draw significant blood, which as Mr Smith said is a poor lubricant & corrodes aluminum....