Here's some tough love, If you think that you PASS, you don't.
Just because you aren't called out on it and are "accepted " does not mean you pass 100% as a woman.
My rules are dress appropriate for the location, wear something that is flattering to your figure, age has absolutely nothing to do with it, and OWN IT. Confidence is key.
With that, the best you can hope for and get is that you BLEND.
This is my experience.
PASSING is the Holy Grail and the hardest thing to get is a female voice, to me that is the give away.
Anyway just my 2 cents