Need to change out my front tire as a slow leak has gotten worse. I've changed many dirtbike tires, but this will be my first tubeless street tire change.

Just a question for those of you who have changed out your fronts. How do I replace the needle stem assembly?
Main reason I am replacing the tire is because after attempting to squirt some "Slime" product in the tire I discovered that the needle stem must have some type of check valve, because the "Slime" could not pass through the needle stem.(yes I unscrewed the valve from the stem)


Black 2007 Speedmaster 2007 Ducati Monster S2R