87 Tintop, Stock & Carbureted

I've replaced all my vacuum lines, however when I got this vehicle a few weeks ago one of the lines was disconnected and plugged and I'm trying to figure where it goes. (haven't been able to find it in the shop manual) It's the one I'm holding in this photo. The arrow points to the valve which is mounted on the firewall. The valve has a microswitch attached and it has two vacuum ports. One of them has a vacuum line attached that routes to the front of the motor into the intake manifold. The other one is short and plugged. So what is thing and where should this vaccum line route? Thanks.
jor

Got this answered on another forum. For anyone else with this question, it's the idle up for the A/C which is separate from the other idle up circuit. The hose attaches to a diaphragm on the pax side of the carb.
jor

Useful to know. 

Got this answered on another forum. For anyone else with this question, it's the idle up for the A/C which is separate from the other idle up circuit. The hose attaches to a diaphragm on the pax side of the carb.
jor

Thanks for bringing that back to the group. That helps grow our information base so the next fella that comes along may have an easier time finding the correct information.

Thanks again, Eric