I figure the specific gauge cluster was done specially for police use. Many forces specify that a police car must have temperature & oil pressure gauges, but a tach & clock were frills and only added to the cost of a tender for a fleet. A certified speedo was often a special-order but the 140-mph speedo was usually standard on the police car package.

As an example, Chevy didn't offer temperature & oil pressure gauges on 69/70 Big cars but only the police package cars had the special triple gauges in the clock spot. They had the 140-mph sweep speedo as well, so that is consistent with the '67 in the e-Bay auction.