Have the face plate custom made, thats what I did. There is a shop near where I live in NYC that laser cuts plastic and its pretty cheap, I replaced almost the entire front of my G3 Smurf with a custom cut face for $50. I am sure the small piece for the zip bay would be much cheaper to have done and it would be perfect.

http://www.canalplasticscenter.com/index2.shtml

They take jobs via email and send you the result.

My results were very worth it:

http://gallery.me.com/mordaskyt/100013