Gauge cluster needles

[921500Z71]

I recently took apart my gauge cluster on my 92 because the tripometer reset needle did not reset the mileage on the dials and the dials didnt even move while driving. In order to fix it I had to take the needles off of my cluster to get into the cluster and fix the tripometer needle. Before removal I marked where the needles were so I wouldnt have to worry about them being off when I reinstalled them. However almost all of them are off ie voltage reading 16, fuel is a little high, speedo and tach are wrong etc. My question is might there be an easy way to get these needles corrected? Any help would be appreciated. Thanks

[GM-Tech]

Feed the individual gauges a known input and then put the needles on so they match that input.

 

For instance, the fuel sending unit provides 2 ohms of resistance to ground to the gauge to make it read empty and 90 ohms for full. The oil pressure sending unit is the same.

 

The temperature gauge input works just the opposite as the oil/fuel. High resistance is a low reading and low resistance a high reading. It's been a while, but if I'm not mistaken, 100 degrees is around 1345 ohms of resistance and 260 is around 50 ohms.

 

As for the volt gauge, just read the battery voltage with a meter.

 

I'm sure they don't do it this way when the cluster was assembled, but I have no clue how they did do it.