I almost have this vacuum hose routing issue figured out. It's just that because of the different option combinations, there seems to be different ways that they are routed.

The vacuum diagram found in the parts manual shows the basic layout. The diagram shows the fittings at the back of the carb for the large hose for what I assume is the power brakes along with the red striped hose. But, there is another detail drawing showing the configuration with power brakes. It has what appears to be another small fitting.

What would this one be for? Could it be that it is used for the AC vacuum tank instead of the carb stud vacuum fitting?

Finally, does the air cleaner thermo vacuum valve use the small fitting on the manifold in front of the carb exclusively, or are there other configurations depending on options?

For reference, these are my options:

400 w/TH400
Power brakes
Air conditioning

Again, if anybody has pictures of an original or otherwise correct engine, that would be the perfect solution!

Thanks again for all your help!

Larry

First, note this service bulletin that disconnects some of the lines:
http://www.oakmediacreations.com/dtb/docs/68-T-2.pdf

Some pages from the '68 Diagnostic Manual:

Jim,

Do you have factory A/C? Which vac line connects the vac tank to the carb or does it go to the TVS switch?

The AC actuator vacuum is provided at a hollow carb mounting bolt. It's the line that looks like it runs into the passenger side rear carb mounting bolt in the picture above. I think Ames has them.