Give the engine what it wants, stop worrying about trying to hit a specific number or target for timing, turns of idle mixture screws ect. Don’t be afraid to adjust the idle speed screw a little from a square transfer slot either way, give it the idle timing it needs to maintain a smooth idle and not slam in to gear, and make sure to limit the total timing once you establish what it wants for initial if it’s above what the distributor was originally curved for. And the best piece of advice I’ll give is this, once you set one thing, don’t be afraid to re do it once you change something else. All of these adjustments can affect each other.