Will adding a samurai t-case behind my sidekick t-case give me any final drive reduction with both cases in high range or would I need gears in the sami case.

You will get a high range reduction, one of the advantages of the Samurai t-case conversion:

High - 1.409
Low - 2.268

and not just .4 reduction....   It is .4 x your diff gearing.

5.125:1 = 7.175
4.62:1   = 6.468
4.30:1   = 6.02

 

And With Myron's Pink Snatch



And with Trail Gear's Toyota based IFS width / Off set diff / Rock Assult rear housing




T-case mounting and drive line angle should not be an issue.

Should even leave some loose change for custom 3-link brackets and drive shafts.

Pink Snatch? Is that just a cradle for the sami case if put after the kick case? Where is that sold?

Great info guys.  Maybe 33's and a five speed are doable after all.  My 31's have killed my highway power.

Pink Snatch? Is that just a cradle for the sami case if put after the kick case? Where is that sold?

Yes that is ZOR's sammy case cradle.  It is as much a case saver as a mount.  It reinforces the stress points that cause a broken case.  With Myron's poly mounts it shoul dnot be to bad to fabricate it in place under a kick. 

I posted on Myrons forum asking about brackets to swap it under a kick...  That would be the hot snatch and make kick guys SMILE>

I have a 4-door, will my driveshaft angles be off without an offset rear housing?  If I do this it will have to be on the cheap.