ojh, I have a holley 9040 parts carb that does have the brass tube. It is unusable due to the main body actually being cracked (got it at a garage sale for $5... was worth it for the parts). but yes, I understand what your talking about, and I did indeed use the proper gasket. Still a fascinating idea, and just for fun, I'll take the carb apart in the morning and block the port manually just to see if that could be it

Yeah, hoss it's the one I got from you. Maybe a previous owner tried drilling something out or some such thing....
I've swapped base plates, blocked off the choke and secondary vacuum ports, etc.
I give up. I'm back to work in two days, I've got the cash to buy a new carb, so I'm going to. (Plus I really need this running so I can sell one of my other vehicles).

Either way, Thanks again Hoss... although not the intended purpose I received a fantastic schooling on Holley 4160 carbs on account of this.

Drew