I don't know if you'd consider this "dirt," but... At a comics convention I went to last year, Lee Meriwether told a story about how when she was guest starring on TOS, DeForest Kelley pulled the top of her costume forward, looked straight down the front, and asked, "What time is it?"If there is any dirt to be found where DeForest Kelley is concerned, just let me know and I will toss my 'heroes' list completely out the fucking window!
It was a different time and behavior like that was just considered innocent horsing around. See also Kelley grabbing Majel Barrett's breasts in the TOS blooper reel. Ms. Meriwether told the story with a twinkle in her eye. She was more amused by it than anything.