Rallye Instrument cluster voltage limiter - 68 Barracuda

I recently did reworking of the gauge cluster to replace lights in my 1968 Barracuda, and replace both of the circuit boards with ones from Classic Industries.
Everything worked fine for a while after, until the temperature, oil pressure, and fuel gauges started going strait to max travel with the ignition on.
Then I heard an electrical pop with a puff of smoke from behind the dash and now the fuel gauge doesn't work, the oil pressure seems to be working fine, and the temperature gauge underreporting. There is also an issue where the Ammeter will drop, wave around, make a "tick" noise, then return to normal which I suspect is related. The lights will dim and flicker along with this but I couldn't read a significant drop in voltage on the battery with a multimeter.
From my reading around this forum and the service manual it is probably the instrument cluster voltage limiter. The only problem is the service manual doesn't identify the limiter for barracudas, only valiants, so I am not sure which component the voltage limiter is. Looking for limiters online match the Valiant's diagram, but I suspect the limiter on rallye dashes was completely different. Is this circled item in the inserted image the voltage limiter?

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