On some days, Michael Arkush’s interviews with Sugar Ray Leonard would last from 9 a.m. into the night. Other days, the boxing great would tell Arkush to stop the recorder, his mood darkened by the retelling of a troubled past. But in small doses over 18 months, Leonard began to open up about a career full of highs and lows. The result was “The Big Fight: My Life In and Out of the Ring,” a book co-authored by Leonard and Arkush that was released June 6. The book “was about me finding myself,” said Leonard, who grew up in the District and in Prince George’s County.