If you've got a blue dash now, you might be able to swap to green using green led's... however if you want to go from blue or green to say red, you'll have to remove the needles & sand the back of the overlays for the color to show through.
If you just want brighter light that's the same color you have now, use white led's to replace the bulbs & you should be good without any other major mods.
It's not too bad changing the bulbs to led's, as long as you have the proper led bulb base that will plug right into the cluster.
Also, it's a good idea to only change one bulb at a time & test each one in the vehicle. If you happen to install the led's backwards, you won't have to take everything apart a dozen times
I've found the SMD style led's have the most light output & best color of any led I've used in my cluster. They're more expensive, but well worth a couple bucks more.