Union apprenticeship sign-ups near Omaha - what worked for you?

I heard of an apprenticeship with paid on-the-job training for people changing careers. I have read a lot of threads here and could not find my exact situation. The application needs a diploma or equivalent, a driver's licence and a short aptitude test. How hard is the test?

Visit the training centre in person if you can. Seeing the classrooms helped me decide.