Transgender identity has changed a lot over the last several decades. You therefore shouldn't expect someone who lived before that to have used the same vocabulary and labels we use today. You also shouldn't force them into a binary gender bucket. There is a wide variety of transgender identities and it isn't exclusively about going from man to woman or vice versa.
When you aren't sure of a person's preferred gender identity and pronouns, you are probably better off using general terms like they/them/their as the Wikipedia article does. You should never use "it" like you did in your first post unless specifically told to do so. It is can be viewed as dehumanizing.