The vacuum modulator has a nipple and you run a line, usually a steel line with rubber connectors on the ends. The other end connects to a fitting on the intake manifold, behind the Carb. Kickdown cable should be connected to the trans. If not, you need to get one. Cable connects to linkage arm on Carb.

 

let me sort out what is what on that thing and I'll see what I have and don't have. Then I'll update ya on it.

 

you can't miss the cable because you have the speedometer cable and the TV (correct term but commonly called kickdown cable) cable coming from the tranny. Only 1 runs to the carb.

If the TV cable is missing it's doable to install a new one but it gets tricky. You'll want to lower the tranny so you have a better angle

The angle is better with a service lift vs jack stands

and by the way

welcome to the forum and when asking questions, it helps to be as detailed as possible in order to offer opinions, thoughts, suggestions