Ive got the detroit ez locker (same thing) The install was pretty strait forward.
Once you remove the 2 bolt per side to drop out the diff (keep every thing marked as to which side it goes it on, like the rings with holes in them that hold the bearings in)
Then I beleive it was 8 bolts on the carrier (dont mess with ring gear) once you have the bolts out it opens up into two pieces.
pull out the 4 spider gears these are what you are replacing.
powertrax may provide a check system to see if the thrust washers on the outside of the side gears are ok.
then its pretty strait forward.
I think that the install of a lockright is actually different than the detroit, so you should just follow the directions.
I hope that helps I will be installing one of these on my buddies rig soon as well.
If you have any other q's about it PM me. Ill try my best.
Oh by the way you cant get a better improvement for 3 times the moneys!!!!