Check out my new and improved version.
The original grill would break the fan posts if tightened too much.
You can edit the model online on Tinkercad.
Depending on your version of the Duplicator, the stock screws (M3 x 40) might end up being too short and you might have to change them for longer screws. I believe it depends on where they source the fan. Everything fits just fine on my first generation Duplicator with the stock fan and the stock screws.
If it does not work for you, feel free to take measurements, experiment with the model on Tinkercad, and leave a comment here.