i have a 71 with dummy lights and i did the conversion to use the guages and i was wondering what i hook up to get the tach to work. i am running a points system on it what wire do hook up to get the factory tach to work.

The #1 wire from plug the dark brown one. Run it to the - side of your coil!!

yea, tried that. put it on the + side and didn't get a response and then tried the - side and the same. i assume that it would go on the positive side. i guess i will have to check my circuit board now.

i just read your post the second time and saw you said the - side. must still have sleep in my eyes. :)

The Tach wire goes to the negative side of the coil, Pin #1 on the connector.....

i did that and the tach still wil not work. i am stumped!

Tach is no good ! I hate to tell ya that but that is what it sounds like !!