Cruise Seems Lean

This is the passage for the timing vacuum on your block. See if the passage is drilled through.
upload_2021-6-10_16-37-2.png
Then check the face of the main body opposite the white arrow. There should be a drilling there.
Shoot some carb cleaner or blow some air through to see if it goes through.
Holley's website says it should.
Holley 0-4224 660 CFM Center Squirter Carburetor
then click specs

Good illustrations identifying all of the passages and basic concepts in Urich and Fisher. If you find a used copy cheap, I think its one of the better books to start with. It does have some self promotion but still good a reference. https://www.amazon.com/dp/0895864339/?tag=fabo03-20