Ive posted over here before, I drive a Chevy Colorado, to which the Hummer 3 share a lot of parts. one thing that is the same, is our circuit boards for our speedometers, or as I call them, Clusters...
I have been doing custom modifications, color changes for about 3 years now, with over 35 clients.
I happened to pick up a brand new H3 Cluster and I am only stealing the overlay, so I have a brand new circuit board in my hands. I charge around $50/$60 depending on what you want done (This is custom to each person, if you want your tach red, and your speedo pink, I can do that)
Here is one example (this is my own truck)
I would only have one at this current time, but I do offer a mail in service (you mail me your cluster, I modify it, Send it back) but that is not available at this time.