Holley 6709 double pumper 750 carb info

Ooo! OK that makes more sense! So I wanted to use these carbs because I thought they would behave like a spread boar with the smaller primary sand give me better lo end torque, with enough cfm flow for my big block. So bad news is I allready bought the special rebuild kits they need.. so how dose the reverse idler circuit work? Is it something I can adapt to my build? And I don't mind tinkering... actually I kind of love it hahaah