It's really hard to cut out such a panel and getting parts that will still fit each other properly. Usually, there's some loss of material somewhere... What I do it cut the panel out from the inside. To ease things up, I'll use the minidrill to drill in the outline of a large hole in the panel. The 'hole' is cut out, then I use a sharp blade to reach the outline of the panel I'm trying to remove. I'll thin the edges of the resulting hole, and create a new panel fro scratch, either with plasticard or the thick foil of a soda can (beer can works too... good excuse to get one out of the fridge!).
If you have a circular saw attchment for your minidrill, you might be tempted to cut panels out that way. All I'll say about that is: BE CAREFUL. Those saws are thin, bend easily and slip easily out of the cut right into your fingers!
There we go!