it works the cable assembly for the cold/warm air doors on a shaker setup. The "carb air" (fresh air) handle underneath the dash pulls the bottom side of the fulcrum and that in turns pulls the inner cable of the setup - which open/closes the air doors. It all seems complicated for what it is supposed to do...but oh well...
Here is a schematic...
Oh, BTW... thanks to Scott from Harms Auto! without him I would I have no idea what I would do. He went out of his way for me and I really appreciate it.
His shaker conversion kit was excellent and I am finally nearing completion on that project!