is it a silver sticker model or black? I believe if you have the silver sticker model, you would need a new logic card as well. There may also be some small mounting differences as well. Missing holes etc etc...
If I remember correctly, there is no driver for the iris on the logic card on the "non iris" model, So I believe you are out of luck. Perhaps someone else out here has done some sort of retrofit? But the logic cards are pretty expensive, so this sort of mod would not be cheap.
