67 - 273 4bbl and 69- 340 4bbl

correct there is a slight difference in bore diameter in the secondaries where the 67 AFB is the smaller of the 2, but the AVS should be the same bore as the holley you currently have.
If you are using the 67 intake as stated you either need to bore the secondary openings or use a small spacer. I used a gasket thick spacer and 2 base gaskets and that worked.