Install aftermarket tachometer

I'll take a stab at this, there's better than a 50-50 chance, and you can do no damage if the first try is wrong. Red is +12 volts and Black is chassis ground. that's a given. I would try Blue to coil pack "Tach" terminal, and Green for the dashlight. If I am right about the Blue and Green, a 9-volt battery from Green to Black will light the light if it's not burned out. If the Green doesn't light it, try the Blue, but my bets on the Green. If the Blue doesn't light it either, the bulb is toast.

how to install a aftermarket tach II in 01 ford focus