How do you change the digital dash display on the 1984 Buick Grand National from metric to english?

The only button on the cluster just resets the odometer(trip) when in start up, the cluster cycles in eng and metric, so i know it can be done.How do you change the digital dash display on the 1984 Buick Grand National from metric to english?There should be a Metric/MPH button to reset, my Buick does.How do you change the digital dash display on the 1984 Buick Grand National from metric to english?There should be a button you press at the bottom of the display.How do you change the digital dash display on the 1984 Buick Grand National from metric to english?get a scruw driver and get it out