If you are putting anything back in there other than the very same carrier/bearings/shims/ring gear or any combination of the above, yes, you need to plan on doing a R&P setup. You MAY get lucky and not need to, but you should be pulling patterns, comparing to desired results (pressure zone on middle of the tooth) preload on the pinion, and such. If by some chance all that turns out O without fussing over it, immediately go to your nearest lottery and sink your savings into it, because surely the stars are shining on you this day....
That being said, everything I've seen says that installing traction devices in the D30A are a crap shoot.. It isn't strong enough, and cracked cases often result. Understand, this is 3rd hand info at best, I've been thinking about doing the same thing and have done some research. People on Teh Interwebz also say Liberties aren't real Jeeps and can't wheel, so there's that... -shrug-
I'm looking into the possibility of cutting down a regular (read: steel) D30 to retrofit it in place of the aluminum unit, but I suspect it will quickly get into needing a machine shop to make the proper outputs on the tubes, and thus make more sense for me to do a SFA