Thats a pretty broad question. The real questions are:
Is it a direct swap?
If it isn't a direct swap, what modifications are nessassary?
Just from my knowledge I would say the only hurdles to confirm would be:
Can you mount the power stearing pump on your 2.5L?
Confirm the 2.5L and 4.0L (donor) use the same steering box.?
Are the bolt holes on the Manual steering box in the same place for Power steering box?
Will my current steering column mount to a Power steering Box or does it need modified or replaced?
These are the steps and questions I would ask if considering what you propose.