have you finished the Arcade mode?
that includes placing first in all the time trials, and completing the Single races on Hard mode.
Then take a look back through all of the sim mode to find what golds you are missing.
You don't need gold on the license test, only bronze.
My guess is a few of the time trials. Or all of them.
As a hint, each race is worth 0.213% So it looks like you may all of the time trials left to do.
#10 is the hardest part of the game.
Good luck
AO