Take a 3 hour aptitude/skills test along with other applicants. Test includes math skills, thinking skills, mechanical aptitude, visual comprehension, etc.
If you pass the test you will be scheduled for an interview. The interview was a few weeks after the test.
The interview is usually conducted by two groups of two people, some in management, and some representing the union officials.
After a successful interview a job offer is extended.
There is a week-long orientation process before being placed within the plant (you have no say which department you're going)