Far as I know nearly all vehicles (yes even obd2) until the last few years have narrowband gauges, the exceptions being some VWs and German/Euro cars. So if you have an oxygen sensor on the 89 at all, it’s a narrowband. That said, I’m not surprised the gauge isn’t working, you’ve probably tapped the wrong wire.
If the O2 is dead, the engine will run rough and get poor mileage. CEL will come on too. I assume these symptoms are not there.
You bought the right gauge. Only one question, is it hooked up wrong or defective? I suspect the former. Easy to find out though. Check with a voltmeter, the signal should be 0-1 volts and jumping rapidly, tick-tock, on-off. Use an analog voltmeter to see it jump. Digital ones don’t respond fast enough. If it’s just on steady, or not a 1 volt reading, you’ve got the wrong wire.