mines off by 2 mph at 25 and about 15 mph at 65. how hard is it to put a new one in a mirada?

 

It is probably a matter of changing the speedo drive gear in the transmission. A 15 minute job. First you need to figure what gear you need. It goes by tire size and gear ratio of the rear end. I don't have one handy the service manuals have a chart to help you figure what you need