The fuel tank sending unit is the same, regardless of if the car has the light or not. I would say, if you know you do not have the circuit board con the cluster, then your car doesn't have that option, and perhaps you put a bulb socket in a spot that didn't have a bulb in it before.
The low fuel indicator is part of the "Convenience Group", option ZX2, which included the interior light delay timer, a headlight on warning buzzer, underhood light, intermittent wipers, vanity mirror on the pass side visor, and I think some floor mats. If you do not have any of these other items, then you wouldn't have the low fuel light, either.
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Joel Adams
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