Assuming you will be using the sensors and wiring off the existing motor, the only thing you will need to change is the harmonic balancer (differnt sensor ring) and possibly the timing cover (crank sensor mounting is not the same).
Replacement late model timing covers have provisions for mounting either the early or late model crank sensors, so if it was replaced within the last few years it may be okay, but the balancer will still need to be changed.
Everything else should bolt up without a problem.
David