Depends if you have access to the entire vehicle since you will need much more than just the motor. For a 2000 to work you will need the engine, transmission, ECU, complete engine and trans wiring harness, fuse and relay panels, pats module and transceiver unless you send the ECU to have the PATS security deleted, radiator, most of the fuel system, and some other odds and ends. There will be alot of custom wiring involved, especially to get the dash to work. If they are both 4x4 then the transfer case is an issue as well.
A pre 1995 engine would definitely be less work since there is no security system, and the fuel systems operate at similar pressure.