Jiri,
Conversion would not be enough. You can only fly in Brazil if you are a brazilian citizen. Or, if you are flying an aircraft as an instructor, and just for the period of time necessary to form a pilot able to fly the one you are instructing him.
Só, if the intention is moving to Brazil without the citizenship... forget it. Politicians are conducting a lobby to change this, but local pilots will keep it away from their jobs. Even thought seems to be a lot of jobs available, that is not the true.
Find a good and charming brazilian lady, get married, and apply for the job. I did it ! And worked pretty well. Brazilian women are the best, and the paycheck here is really nice too.