Fuel and temp gage

That puts it on the high probable list. Could be that power is not getting to the limiter. These units plug into the circuit board and over the years connections go bad.
I don't know off hand if the two gauges share the same fuse.
If you have a test light, that will make for quick analysis of where electrical power is going. I like it better than a multimeter. Just touch some key points on the circuit board.

Since the likely problem is the Limiter, you might want to consider buying a solid state version or making your own. The OEM mechanical limiter can fail in the closed circuit mode (apparently yours failed "open circuit"). If they fail in closed circuit , it will fry your gauges.
it looks to me that both gauges run off the same
That puts it on the high probable list. Could be that power is not getting to the limiter. These units plug into the circuit board and over the years connections go bad.
I don't know off hand if the two gauges share the same fuse.
If you have a test light, that will make for quick analysis of where electrical power is going. I like it better than a multimeter. Just touch some key points on the circuit board.

Since the likely problem is the Limiter, you might want to consider buying a solid state version or making your own. The OEM mechanical limiter can fail in the closed circuit mode (apparently yours failed "open circuit"). If they fail in closed circuit , it will fry your gauges.

Limiter! here is picture of wiring diagram
That puts it on the high probable list. Could be that power is not getting to the limiter. These units plug into the circuit board and over the years connections go bad.
I don't know off hand if the two gauges share the same fuse.
If you have a test light, that will make for quick analysis of where electrical power is going. I like it better than a multimeter. Just touch some key points on the circuit board.

Since the likely problem is the Limiter, you might want to consider buying a solid state version or making your own. The OEM mechanical limiter can fail in the closed circuit mode (apparently yours failed "open circuit"). If they fail in closed circuit , it will fry your gauges.
where do I buy a solid state version Limiter?

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