It's normal now for older people to be getting diagnosed with aspergers or autism because it wasn't really that well known back in those days. But yeah, seen it on BBC documentaries where elderly people have been like "turns out I like being alone so much because they diagnosed me with aspergers syndrome."

I would just not mention you have autism/aspergers to people without first getting their opinion on it, if you ask them what do they know about it or think about it, if they give a negative response then don't bother telling them. If they ask why you're asking, simply just give them some excuse like you were just wondering cause you heard about it on the TV or something.

If you apply the logic of like how gay and lesbian or transgender people won't 'come out' to a person until they know they are safe to talk to about that stuff, same kinda thing applies to autism, otherwise it can bring you some really heartbreaking drama when people won't accept you. For example my ex used to say if he knew I was autistic he wouldn't of gotten with me, stuff like that makes me so angry but it's so common sadly.

Honestly you do not want to go through the whole drama of people judging you and bringing you grief because of them being too selfish and closed minded to accept you. Anyone who is horrible to you because of something like that doesn't even deserve to talk to you as there are much nicer and accepting people out there.

Good luck, hope everything goes well.