Greg Cox wrote:
These days, of course, you can always check Memory Beta to see if an old TV character has ever been assigned a first name. If so, I try to be consistent with the earlier usage . . . but have been known to play the "actor's first name" card on occasion.
Which isn't always helpful when a character has been given different first names in different sources. Mem B's entry on Mr. Leslie was ambivalent about his first name. I can't even remember which one I went with in Forgotten History