Since you already bought the Fan Shroud, then install it.
Personally, I'd re-position the Fan Shroud properly and ignore the cut hole, which is not harmful to the car in any way.

I just wrote a DIY for cooling system partial overhaul, you can see the steps involved below:


http://www.xoutpost.com/bmw-sav-foru...16k-miles.html

Personally, if I could reposition the shroud correctly, the small hole would not be a big deal.