Tach Signal Wire

Hi I have a 1994 ponitac sunbird and I am wanting to hook up a tach but I am unsure of the color of the signal wire so im kind of stuck till i figure that out but if anyone can help me out that would be great

power up the tachometer by puting wires to the fuse box and as for the tach singal wire dont try n looke for one just put the tach signal wire from your tach to the pos or maybe neg side of the ignition coil hopefuly this helps :]

as for the ground wire i could never find one on my car so i just quit and put it to the neg side of my battery :/