Can someone plaese tell me where to get a tach signal for my L7 mira

Can someone plaese tell me where to get a tach signal from?
its a 2000 mira and its a external tacho

white is for light
red is the +
black is the -
green is for the coil

where do i conect the green tacho wire

cheers jim

is it a tacho that suits 3 cyl motors? might not work if it meant to be a coil input as the L700’s ( and the M100 3 cyl Sirions) have the tacho signal come from the ecu, pin 29, red with yellow stripe and don’t think the signal will be powerful enough to drive the tacho, i had this hassle getting a jdm tacho dash working i my EJ-DE swapped L200.

ill give it a go, and we will see