Being a mechanical and car maniac doesn't make you any less of a woman! Surely you'll face sexism because of it, but don't give up what you love if you don't need to, isn't it part of you? Just go ahead with it and to hell with others.
In Brazil you'd most likely pass as a "caminhoneira", bad rep due to sexism but definitely a woman, that's what mattersIf you find a guy who does love you as you are, including you being trans and him seeing you as a woman, go for it as well. If not though, it's most likely better off to be by yourself at this point, as most men are unfortunately too sexist, transphobic and close-minded to know better. If you know a relationship won't work, spare yourself the pain, you'll be doing yourself a favor. Try your best to be happy by yourself, as who you are and nothing less: if you aren't happy by yourself, you won't be happy with a partner either.
That said, no idea if it's your case or not, but you might not even like men to begin with. In my case I'm bi strongly pending to the lesbian side. When I started HRT, I'd already gotten strong crushes on other girls (and the occasional crush on male friends): I'd figured that since I never had an actual relationship, I wouldn't be able to tell if my crushes on women were due to T or what

, so I waited a bit.
Turns out my T went lower than cis women levels and I still like women just as much, the only difference being less annoying male libido. So much for thinking I liked men

Really, if you've gotten so far as to have FFS and VFS, if you've learned female mannerisms and such, chances are you'd probably pass anyway and only be stared at due to looking like a butch lesbian and having the hobbies of said stereotype (still bad, but not half as bad). Even if it isn't the case right now, secondary sexual characteristics tend to get neutered as you get older after your 50s, so I wouldn't worry.
If I were you, I'd seriously reassess whether you "pass" or not. If you don't that's not the end of the world either, you don't owe anything to this damn transphobic society, just try to be yourself and live on without a care in the world. If you look androgynous-ish though, with a feminine face but broad shoulders for example, just speaking up would most of the time automatically pass anyway. That's how it goes for me: my face is still the most masculine part of my body, which makes people stare at me and is my next goal to take care of, but since my voice is feminine
nobody mistakes me for a man if I speak up.
When people look at you, they'll receive several subconscious signs from your appearance, which include gender appearance. If they can't 100% decide just from your looks, the next deciding factor would be your voice. And if you've had VFS, well, that takes care of that.
Be strong. Women have no need for weakness: society only makes it seem as such so that they're easier still to be manipulated and used by men. Be open about your hobbies, let nobody question them, and if some unassuming guy
does question you just ask them why is it that you can't do what you like.
Why?
Most just react by being flabbergasted, lol.
As for working as a woman from now on, excellent suggestions have already been given.
I'm not too sure if opening up a business is adequate or not, considering any business carries a risk to it, and requires investment: if it doesn't work out, there goes your investment, which means less money for transition. But it's definitely a great, appealing possibility (especially with what's been said about a women-friendly shop), and if you're able to secure a safety margin you should be fine.
Be yourself. Nobody else has the right to tell you who to be.
Best of luck.