Very, since LC's and Mini's don't share the rear diff. You'd have to swap the LC axle under the mini, and then you'd have to figure out how to deal with the offset diff of the LC. All in all, not worth it.
I haven't done it, but it's been my experience that nothing's as hard as you first think.... It just takes longer than you think! It's not too bad to get a Toyota locker in your truck. Just a drill a tap a grinder and a little welding. Don't jump in if it's too deep for you though, but remember, you can hire moble welders.
if you're not running huge meats, or doing any crazy hardcore wheeling, a lock rite will work nicely and is an easy afternoon install. i put one in the front of my 4runner in an afternoon while rebuilding my axle. btw, this was my first experience w/ tearing into an axle or messing with the diff. works great on 36" IROKS