So, you're missing the unit in the fender, thecable to the throttle, the vac hose and plunger switch?

Chained switch? Kind of like a light bulb with a string/chain? The only one I've seen are the vacuum shut off switch that's at the top of the brake pedal..black screw in barrel and a white plunger hooked to a big vacuum hose. OTOH, it been mostly '85's and '86's that I've rooted around in that area of the dash.