I believe you can, but from what I recall, it is not a direct bolt-up swap - I think there is a difference in the clutch/input shaft area.
Edit -
Sorry - I just realized that your 1.8 is an automatic, my earlier reply was considering a 1.8, 5 speed to a 1.6, 5 speed - an auto to manual swap is a lot more involved - in addition to the mechanical aspects of the swap, you'll have to consider the electronics.