How to test Tachs 67/68 Ford Mustang and Shelby?

[Kent]

I´m still thinking about how I can test my tachs here. I have a 65 Mustang here with no tach and would like to use this engine as the bench. So would it be ok to take a 1.5 ohm ballast resistor between and put it in line with the ignition switch to coil +

I read on some other forums that some people don't use a ballast resistor and only put the tach in line from ignition switch to coil +

Is there maybe a drawing or something how to do it right, thanks...

[67350#1242]

Even non tach cars have the resistor wire in line from ignition to coil.  You should be safe putting the tach in series with that circuit. 

[67 GT350]

I have a diagram from Phil Severance for the Shelby tach for a 66, would you like that?

[Kent]

I think that could help, you have my e mail from last week I think, thank you.

[67 GT350]

Hope this helps