I think you need to disclose right at the start of the interview because it will settle any misunderstandings, and actually make you look proactive. Just be like, “Btw, I do stutter sometimes. I do my best to always push through everyday, despite it. It’s a challenge but it’s helped build resilience in me over the years. I know what I want to say before I say it. But it can just take a little longer for the words to come out. You don’t need to fill in my words to help me out. But if you need me to repeat something I will. Come in there sounding like they need you, and not the other way around! Go in there sounding like you’re the freaking boss and you stutter. And you’re teaching the employees how to interact with you. You tell them who you are and why stuttering has made you a better person. And give good eye contact and smile, because that’s what good speakers in general do.