Speedo year / gear ratio info

[BIGRED]

Our wagon is a 1980 and had 3.46 gears. A turbo motor was dropped in it and a couple of years ago I changed the rear end to 2.88 gears. That caused our 80 MPH speedo to be off about 10 mph.

I came across a cluster that has a newer speedo in it. I have not been able to reference any numbers on it to any numbers I can find on the EPC to see if installed, will it but back into place the proper speed. Or, do the gears in the speedo have some identification that ties them to the difference ratio?

The face of the speedo has 123 542 27 57 between the MPH and VDO and goes to 120 mph.

Thanks for the help
Don