well you can make gauges that takes a long ttiiimmeee...
Or you can edit the bitmaps making gauges alot more simply. This is simply choosing a gauge in a gau format.
opening it and messing around with it. Then putting it back into flight sim using cfg or what ever.

here is the link its called fs 2000 gau and bmp utility
it works with 2004 http://www.simviation.com/fsdesign_panels1.htm