Need Vacuum Line Help

I discovered a vacuum line on passenger side of engine bay today, not hooked up. It is probably 3/32" ID, and has a white vinyl or plastic extension where it would hook into another line. It was laying up by firewall, and is connected to a diaphram gold colored piece junctioned at the heater hose. Probably the hot one.
Kyster says it would hook up from the heater control valve somewhere, and to look for where it would have to exit from the dash inside forward thru the firewall.
Cannot find connection to save my soul.
Any ideas ? If anyone can help, I can e-mail the picture of this area and components.

Thanks, Boatman ......... Vinterrv@aol.com

Boatman... Just went and looked at my 80 with A/C. A vacuum line exits the firewall just before the distributer as you are looking from the passanger side it t's off with one side going to the valve and the other picks up vacuum all the way over on the drivers side by the Brake booster. Mine snapped off a while back right at the firewall. Its the only time my feet were ever cool , A/C blew straight to the floor.

Yes,Boatman, as the previous post said it goes through the firewall with two other vacuum lines the same size(on my 82 with AC)on the passenger side of the distibutor,and they end up eventually at the heater control and actuators.I was able to repair mine by inserting the two broken ends into a larger piece of vacuum hose and securing it with nylon ties until it can be replaced.

Collector - Thanks for the reply. Is this line dedicated, or is it T connected somewhere? Doe is just need vacuum only ? If so, I can T it anywhere for that.
Or does it connect into one of the heater control lines that plugs in at console? I am getting ready to take console apart and track it down somewhere.
Does this make the AC operate more efficiently?
Thanks

Tell you what,Boatman,I will be working on the vette later today and I will take a look to refresh my memory and let you know.
Jules

E-mail is on the way,Boatman.

Thanks again Jules. MKapp and I have been mailing back and forth on this. I sent him your msg.
Boatman here, and have a Miller Lite on me.

One Miller Light,bottoms up on you,count on it!

Cool on the Lite. Get back to you soon on the routing, couple days, 84 here today.