There are several brands of what we call lunchbox lockers. These are locking mechanisms that replace the spider gears in a standard differential carrier. Here is a pic of the Aussie Locker brand



Installation of the locker itself will be the same in any standard carrier in the front or rear axel assembly.

The first step is to jack up the axle and support it with jack stands. Here is an example of how to remove the axle shafts for a D35 rear axle
The only addition to this procedure would be the removal of the C clips holding the axle shaft in if you have them. This axle did not. However if that is the case, remove the differential cover and remove the C clips before doing the following



To start, jack up the rear, remove the wheel and brake drum. It should just slide off.



Next, there is a small plate with four bolts on it that holds the axle in. These must be removed next. It is not necessary to remove any part of the brake assembly.



If you have ever wanted an excuse to get one of those flexible ratchet wrenches, this is the time



The plate should slide freely off the studs like this.





Next, the axle should be able to be removed. However if you have C clip axles, you will have to remove the differential cover and rotate the carrier to the appropriate position and remove the C clip first. To remove the axle, you will need a slide hammer. These can be rented or borrowed from many parts stores.

If you are installing a lokka in the front axle, the procedure is a little different. First jack up and support the front axle. Remove tires.



If you have a central axle disconnect (CAD) it is now time to remove the differential cover. It is hard to see in this pic, but there is a snap ring on the passenger side only. You must remove the snap ring before you can get the passenger side axle out.



Removing the axle shafts can have varying amounts of difficulty. First remove the brake caliper using a 13mm socket to remove the two bolts that hold it on



Then using a 13mm socket again remove the three bolts holding the unit bearing in the steering knuckle



If you are lucky, it will all fall out without any problem.



However it doesn't always happen that way. So next using needle nose pliers remove the cotter pin and lock nut on the end of the axle shaft. Pull the disc off the studs. Then using a 36mm or 1 7/16" socket remove the nut holding the axle in the unit bearing.



Then smack it with a good sized hammer on the back side and work it loose.