The certified speedometer requires the compatible PCM. As I understand it there is greater resolution to the cluster. The calibration procedure is very unique with those too. When you first install them (into a Police Package Tahoe) the tach and speedometer don't function. Basically, you bring the truck up to a certain speed (I think it's 60mph) getting pace from an external source, drop it to neutral and redline it. This sets a base calibration point. These clusters are electronically very different from the ones in our trucks. Getting it working on a 454 would be even more interresting because they have a lower redline than the 350 Vortec does.
Check out the speedometer circuit board:
I figured on picking up a 120MPH one and fitting the 130 face to it. I noticed the scale of the 130mph one allows a little more sweep. Seems now the supply of the 120's has dried up.
I let this project go a long time ago...
I would be interrested to hear what additionally you find about about them. Good luck!