Okay, some more questions:
From what I can tell there is linkage that opens the secondary throttle blades when the primaries get to a certain angle. This works unless the little pin prevents them from opening. So what conditions must be met so that the lever moves so that the pin isn't obstructed and the throttle blades can open? Is it just an engine temp. thing? Hope that explanation's not too vague.

Second: It's also my understanding that the carb will automatically go to high idle mode until the throttle is blipped, and then releases down to low idle mode. Is this correct? Does anyone care to explain how this works, and if it's not working, what should I look for?

Third: Facing forward from the carb, on the driver's side of the fuel filter inlet, there is a little opening and tube. Is this supposed to be plugged? Is this some sort of vacuum dealy?

Fourth: Is there supposed to be a (I assume vacuum) hose sticking starboard from carb that runs back toward distributor area?

Fifth: I gather that once the secondary throttle blades open the blades on the air horn will open as well. There is some linkage connecting the air horn blades to some sort of plastic cylinder, and while the engine is running this is alyways holding those blades closed, so even if I could get to the point that the secondary throttle blades open, the air horn throttle blades remain closed. What's going on here? What controls this vacuum signal?

Any help and suggestions would be greatly appreciated. Thanks in advance.