Quick Tuning Upgrade Holley Vacuum Secondary

Good to know, the one I have is a 670 model, have never bolted it on anything.
If I ever find time I may put it on my duster, because it has an electric choke.
The double pumper I have on it now, I dont have a choke cable hooked to it, so starting sucks, because it is just a pleasure vehicle, not started much.
I also have a 670 Holley SA. I haven't put one of these on it yet, I'm actually not using the carb this last year.