I just changed one of mine. (99 230) It isn't hard, but it can be frustrating. You have to unlock a few layers to get to the cluster.
The best advice I can give is go slow and be careful. The plastic tabs have a real tendency to snap off, especially the ones that the various screws, screw into. There isn't much space, for either you or the various pieces to come out. And take even more time putting it all back together. It's pretty easy to get a misalignment.
My $0.02 (feel free to convert to the currency of your choice).