Quad carb setup information help

Tim, I’m reading the holley instructions on their carb tuning. Here’s a line about the slot and idle adjustment……. "The Tslot should be exposed slightly as shown. Not having any showing will cause a stumble as you apply the gas from it going lean. Having too much exposed will feed enough fuel to the engine at idle, to make adjusting the idle air fuel screws not have any effect, making it idle too rich. It is best to set the Tslot so the opening that is exposed is as long as it is wide, square. After doing this, make your idle speed adjustment using the secondary idle adjustment screw.’

I’m not home until Sunday night late to look at my carbs and haven’t found a pic that shows a secondary idle speed adjustment. Do you know if all holleys would have that? Just trying to educate myself a little more on what I will be doing. I guess I will pull both carbs off to verify from the underside of t slots?
I’m sure this will end up a long process until done.lol
Rod