Center carb 340-6

Since I have a 440 6bbl, a couple of questions:
Are your outboard carb idle mixture screws accessible, IOW no lead plugs? Having those adjusted properly was a HUGE part of getting my 6bbl dialed in.
Reading this tuning tip was THE epiphany for dealing with the biggest hurdle in having a great running, idling 6bbl:
View attachment 1715464024
going to try that simple check with the bleed holes - if it is set correctly it won't increase or decrease ? Think end carbs still have the plugs