Can someone help me identify this part
 

1989 F250, 7.5
Passenger side of engine, very close to firewall and to the left of the blower motor. It is about 2" round and has a very thin white covered wire coming out of it. It has a flat metal thing on the bottom that pivots if you move it. The wire literally fell apart in my hands. In fact I don't even see a wire...just the groove where a wire might go. I can see a picture in my manual of it in some diagrams, but it is not labeled as to what it is.
Thanks...

Looking at it closer, it doesn't look like a wire was inside. More like a very narrow tube of some sort.

heater box part??? Could be a vacuum line for your HVAC box.

Can you get us a picture? I know those old Fords inside, out and upside down and that doesn't sound like anything I have ever worked on before.

Attachment 1303

Hopefully this attaches ok

Vacuum operated solenoid for your heater box.

What does it do?