I'm new to Suzuki's as of a couple weeks ago.  I got a '96 Tracker for my wife.  The seller threw in an extra set of 5.12 thirds.  Do those fit Samurai's?  Anything else they would be useful for?

The front gears will work in both the front and rear of a Sami. The rear will not as the ring is larger and will not fit with out using a hybrid rear housing.

I'm new to Suzuki's as of a couple weeks ago.  I got a '96 Tracker for my wife.  The seller threw in an extra set of 5.12 thirds.  Do those fit Samurai's?  Anything else they would be useful for?

Welcome to zukiworld. We'll need to go wheel'n sometime.
http://www.zukiworld.com/forum/index.php/topic,26564.0.html