I actually run a mini-spool, it replaces the spiders and the side gear, as well as the pinion block.
A full spool replaces the whole carrier, the ring bolts right to it, not made for our applications, but made for just about every other axle, common in drag racing and drifting and such, light, strong, nearly bullet proof.. but, like I said, no one makes one for zuks that I know of.
Welding does the same thing as a mini spool, yeah they are locked full time, wears your tires and is hard on axles, but I haven't broken one on the street......yet...lol I have broken an axle in a fullsize with a full spool, but I was farting around and deserved it, it was about 20 years ago though... on a Dodge...
The Minispool I use was actually made for a samurai, but fits the trackick too, got it from Randy's Ring and Pinion.
Read up on the other lockers available for the more popular axles.. the lockrites, and ez-lockers are looked down on by almost every hard-core off roader, since they were invented.. I know, cause I used to roll with a lot of guys like that. A full locker, like a Detroit, is a true posi and works much better than the lockrite type of locker.
Folks messing with Suzukis sometimes forget that the other full size carrier replacing lockers... like the one pictured below, is really much much better than a lockrite style, these are tried and true, and sworn by, by TONS of offroaders.. I sure wish someone would make one for our trucks... They are available used for about the same price as a lockrite..