Running rich....To big of a carb or?

DOES it shut down with the idle mixture screws turned all the way in?

Yes I can turn the idle mixture screws in and cough the engine out.

However, while running at and idle around 750-800 rpm. If I turn the mixture screw in until it stumbles, and then back the screw out a quarter turn and repeat the same step on the opposite mixture screw. It runs good.... But I checked the position of the screws and at this point both screws are a half turn away from being fully seated. Not sure if that's right or not. But if I back them out any further than a half turn than i believe it will richen the mixture even more. And I'm aiming to lean it out.... Not richen it up