If you follow these instructions, you can do it yourself for about 20 minutes of your time and ~$22.90 in parts. Also, once you replace the bulbs with LEDs, you shouldn't ever need to replace them again. This picture is of one of the new LEDs connected to a 12V power source.
I got the idea for this instructable from a 2007 forum posting at http://forum.chryslerminivan.net/showthread.php?t=6856 which provided the basic instructions on how to disassemble the dashboard.
Step 1: Parts and tools
The instrument cluster of the 2001 Voyager needs 8 bulbs. The replacement bulbs are PC74 (a #74 bulb with a twist-lock holder for mounting). I ordered QTY - 10 of #T1.5-B Blue LEDs (8 plus a couple of spares) from http://superbrightleds.com. They have LEDs for just about any vehicle, and not just dash bulb replacements, but others as well.
A small pair of needle nose pliers - to twist out the old bulbs and install the new LEDs
#1 Phillips screwdriver(s) (short and long reach) or a combo type with a drive extension (preferably with a magnetic tip).
Small flat blade screwdriver - for prying a cover later.
Step 2: Getting started
Also, adjust the tilt the steering wheel as far down as it will go and WITH THE VEHICLE OFF and the PARKING BRAKE APPLIED move the gear shift lever to its lowest position. This will help in later steps, providing better access and some wiggle room for the dashboard cluster.
In this step there are two(2) Phillips screws that need to be removed. They're located under the upper edge of the instrument cluster bezel. Remove these two(2) screws and set them aside.