A situation I would like to set up for the close-minded would go something like this:
You invite a co-worker (classmate, or whatever) to join the family for a holiday meal, maybe on the pretext "Oh, she's from out of town and can not be with her family this holiday."
Your guest is vivacious, funny, friendly (good looking would help) and gets along great with the whole family. She spends the day, afternoon (or whatever) and everybody has a great time.
After she has left and everything has settled down, when the family has gathered for some quiet time, you ask them how they liked Ms. So-And-So. when a few people have commented, you respond, "Yes, she's nice. Too bad about her past." Then you wait for someone to "bite" >

[If I had the chance to do it, I'd even consider hiring an actress to be the "guest"!]
I really think that if "normal" people got to know a post-op TS as a person BEFORE they knew about her past, it would go a LONG way toward fostering understanding and acceptance!