Opinions about mileage odometer correction tool

[Middleton]

I recently replaced the instruments in my car, but now the new odometer reading seems to be excessively high. I'm considering two possible solutions: disconnecting the speedometer temporarily or finding an instrument to adjust the reading. Does anyone have experience with either of these methods? I recall that older cars used a cable connected to the gearbox for the speedometer—does it work similarly in modern vehicles? Any advice would be greatly appreciated!