Job Interview

I have a job interview tomorrow for Community Corrections Victoria to work as a Community Corrections Officer - essentially a Parole Officer. I have been going through the recruitment process now for about three months - with online testing, telephone interviews, personality tests and so on. This is a huge deal for me - I am doing my Masters in Criminology, and I badly want to work within the justice system. It is actually more than just a job interview - it is an "assessment centre" with an interview, group scenario with other applicants, written testing and computer testing. All up it will be about four hours.
Suffice to say I am a nervous wreck! I'll let you know how I go.