I believe that is the incorrect tube assembly. If you look closely at K19 A10, pg 258 it states via a note that the AIR valve assembly is installed the same as a 327 2bbl (found at K19 A9, pg257). This indicates the tube assy you need is item #15, part #3888364 (note the band for attaching the valve to the tube assy). I believe you will find that K24 A2, pg 267 is for non A.I.R. (smog equipped engines), and it shows one bung at the fill tube, with the hose routings for both the 4bbl and 2bbl carbs (the picture is confusing, but is showing the location of the bung when the fill tube is installed for the two applications). If I'm wrong, I am sure others will correct me, but that is my opinion on your questions - hope it helps.