You mean LEDs? It's possible, but a little more complex. You'd need a simple circuit to do current limiting. If you want to be able to dim them, that's a bit more complex. Take a look at this:
http://www.dansdata.com/caselight.htm
It's a basic primer on rigging up LEDs. The 5mm variety are more than ample for the purpose of lighting a dashboard. He also has a writeup on using Luxeon Stars, but that would kill your night vision.