A couple more holley 1920 questions

It just doesn't make sense for it to be there, unless it is an auxiliary ported vaccum port. But that is the port right below it.

Check this Mike's Carbs video on their remanufactured 1920; it shows this exact area soon after the video starts around 12 seconds....no hole!
http://www.carburetor-parts.com/Holley-1920-Remanufactured-Carburetor_p_2934.html

IMO.....someone has been dorking with this....plug it with a soft metal material and/or JB. I can make very clean holes with a drill...!!