You can schedule an Uber up to 30 days in advance and lock in the price. Expect about $60-$75 each way, as low as $58 if you book in advance off hours on Sunday. If you want a little bit of an adventure, you can take public transit for $10/person there or back (round trip for $10/pp if you take metrolink both ways): Metrolink Anaheim --> Union Station --> Subway direct to universal. Metrolink doesn't run very often. If you opt to take Amtrak back you're looking at ~$18. There is a Sunday 10:20pm Amtrak from Union Station.