Please do yourself a favor and get to a LAX hotel the night before. Unless you want to wake up at 5AM in Anaheim and drive to LAX on Monday morning, you are going to miss your flight. And even that is really pushing it if you need to return a rental car. More likely, you'll need to wake up at 4AM and leave by 5AM. Budget 1.5 hour for the drive, 1 hour for the rental car return, and 1 hour to clear security.