You can put this and try and hide it
Mini Inline LED Controller for RGB Million Color LEDs & Strip Lights
You can still use your stock dimmer switch so that in line controller isn't necessary.
Then I would just wire it to the led strip, run the wiring out the back of the cluster and have it come out at the bottom of the dash. That way you can have the controller hidden but still accessible.
If you use an led strip in the cluster you can solder it to the cluster for power, just like an led.
Nice, post some pictures when you have it all done.
And if you click the link in the post you quoted it will take you right to Oznium's site to buy it.