Who ever did the gauge arrangement was definitely a hack and if you could get 3 matching gauges of the same manufacturer that would definitely clean it up. Same goes for the Tach, that supposed to be mounted from the back of the cluster not front so the cluster panel was also hacked up. I think if you could get the factory Tach as well as the Bat-O-Meter for the original instrument cluster followed by the other 3 gauges that would make a nice combination specially having an ammeter as well as a Voltmeter would be some combination and that's not are farfetched idea either because GMC actually had such a combination on their later H & J series 7500-9500 trucks.