You mean you replaced the circuit board right? Have you replaced it with a brand new one or an original one?
Instrument Cluster Circuit Board with Built in Limiter 1972 - 1976 Duster Valiant Dart A-Body
I have found this modified board on vansauto.com with a built in limiter. I assume it works with the stock gauges. Is there any test/review of it on this forum? I mean we all know the BS we had to go throught at least once with the IVR problem.. So it might be a good alternative instead of checking the board itself, the gauges, IVR etc..