That is an interesting idea, but the simplicity has flown the coup with that idea. The master cylinder has to be upgraded, the steering has to be bastardized to make it work, and you'd have to adapt the brake lines, etc.
In general you'd be looking at much more of a pain in the butt than it would be worth. With what I have built, and am building the KISS theory definitely is very prevalent, that's why I made it. It spells out
Keep
It
Strictly
Suzuki!
It makes things so much easier for repair if you have to take your truck to a shop for repairs when your away from home if everything is from pretty much one place, stock Suzuki Samurai!
The way I'm looking at it is, the easier that it is to find replacement pieces in the long run, the better the design.
As for the TTB diff, it would be next to impossible to be able to utilize that diff with the sidekick housing, or even the TTB knuckles would not be easy to use on the same setup.
Just a thought.