Sorry if this has been covered before, I ran a couple searches and couldn't find anything which quite answered my question.   

I've got a '93/'98 LWB Sidekick (cobbled together from two parts trucks) which will be getting a VW diesel in the future.  I'm planning out the swap now, and I had assumed that the highest R&P gears I could get would be the 4.30s out of a 3-speed SWB Trackick, until I noticed that the Samurais were available with 3.73 gears.  I'm not very familiar with the Samurais or parts interchangeability between the models, however.  Can the 3.73 gears be made to work (without major work like widening the sammy axles and swapping them into my Sidekick)? 

Otherwise, I'm looking at running 31"-32" tires with the 4.30s to get the freeway RPMS I'm looking for, which isn't that big of a deal to me, but I'd rather keep my 235s unless the Sammy gears are going to be a bunch of extra work.

Thanks!

I don't know how you would/could get samurai gears to work in the rear axle of a trackick.  The bolt pattern on the ring gear isn't right.  The carrier bearing spacing is off, for trying to run a samurai carrier.  I would doubt the pinion bearing spacing is right.
Your best bet would probably be to run a complete samurai rear axle.  But the samurai axle is about 3" narrower than the trackick one.  So that wouldn't work real good either.
I'd say go with 4.30s and avoid the hassle.

You could build a reverse hybrid housing and use the Samurai center section with Tracker tubes on it.  Not sure it would be worth the extra .6 though.

Yeah, that's basically what I figured.  I can get the final drive ratio I want by going with 4.30s and 32" tires, so it's not a big problem. 

Thanks, all!

Ah, bigger tires.  The perfect solution to gearing issues!