I need to jump in here and i'll probably be the buzz kill everyone hates.
IF YOU CAN GO TROUGH LIFE AND NOT TRANSITION, THEN DONT!!!!
I was in my mid 40's when I started. i was never strong enough to do it when younger but one day i just couldn't do it any more. I knew I might lose everything, become the circus freak and never fit in. It didnt matter.
My point is this, if you can live as you are then do nothing but if you must do it, age does not matter because once you are yourself the concept of "passing" goes away.
One last comment, even the movie stars get pictures photoshopped. Almost impossible to have one of those bodies or faces for real....