Project Calendar

In MS Project 2003, How can I make my own calendar days start an hour earlier? ie I want Sunday, 1st shift to start on saturday at 11:00pm? Monday 1st start Sunday at 11:00pm and so on.
I need to start a project based on 3 shifts starting with 1st shift at 11:00pm and going to 7:00am, then 2nd shift from 7:00am to 3:00pm and 3rd shift from 3:00pm to 11:00pm.

Thanks in advance.
Gary