Carb Help Please
if there is nothing wrong with the carb and it's close to baseline holley tune, then i'd imagine you need to be less than a full turn on each idle mix screw.
probably around .75 turns out. start at one turn out on each of them
then go around the car turning them in 1/16th turn until it starts to idle down slightly, then turn each one back out 1/16th of a turn...
you should be able to get it to where, after they're all adjusted correctly, you can turn one screw in close to all the way and the motor will want to die.