Holley 1920 1 barrel tuning and adjusting

hi everyone
Im trying to find the best way to tune and adjust the Holley 1920 1 barrel carb on my 225 /6.
I completely cleaned and rebuilt the carb,but seems to be running rough.I adjusted the idle the way it says in the oldd manuals,but now it seems to run even worse.I dont want to mess with the air/fuel mixture screws (if I dont have to)And how do you get the chocke to actually work on these carbs?Mines a 72 Duster.Any ideas and advice on how you adjust your carbs for the best performance is welcome.Thanks