I say "go for it!" Who says a mechanic has to be a man??? Danica Patrick is a race car driver - a woman in a man's sport. I don't feel there are that many gender boundaries anymore. Women are doctors - practically unheard of at one time. They are plumbers, electricians, linemen(women), tractor trailer drivers, etc, etc. More and more men are nurses, stay at home Dads, etc, etc.

You can be whatever you want to be. Follow your heart, and you will succeed!
Good luck.......