Unfortunately, there is no "easily." Its your choice- you're options with the least hassle are: Rodeo 3.5L, Trooper 3.5L, Acura SLX 3.5L, Vehicross 3.5L, or 2002 Isuzu Axiom 3.5L (paying attention to get a specific model number engine, as only some of the first produced for the Axiom may work). All of the rodeo, trooper, SLX and Vehicross are the same 3.5L motor you have in yours. They will all still suffer from the same design flaw that evacuates all the oil and leads to running dry. The Axiom engine was redesigned, and should not (no mention of any similar problems anywhere) suffer from the same issue. It doesn't take any modification, just drop the small block in. They will all cost the same (2-4$ dollars), and the power output is the same. These engines retain the TOD system. If you really didn't care about or need TOD, you can do an engine, transmission and transfercase swap, and never have any issues with oil consumption or transmission failure again.

The 4E30 transmission is weak, the 3.5L engine can be flaky (but is powerful). The TOD clutch packs are the only piece that is truly reliable.

For more information, please search the forum (using the search of course) as I don't have any part numbers or specifics past what I've written at hand.