How to install an aftermarket tach in 1994 mighty max that had no factory tach

I have not been able to get my aftermarket tach to work. The truck has a 2.4 engine and 5 speed manual transmission and did not come with a tach. I have tried to connect the signal lead from the tach both of the post with wires screwed on that are attached to the coil and there is no response at all from the tach. Is there some place that the connection should be made and if so can any one send me a picture.

Look if the tach has power And ground, also look if the sender wire is damaged somewhere, if all wires are ok maybe your tach is gone.