Not sure where you're staying, but RD or late at night are going to be your best bets. The risk of course is that it doesn't open at RD, and you really need to be front of the pack to avoid a wait. We're typically the front of the pack at International Gateway and fast walkers, and still can't get to Test Track without a good 45 - 60 min. wait because those at the front are just so much closer to the ride (we have however had good luck being the first ones on Frozen from IG). Epcot is open until 10pm most nights - the later you can wait, the more likely you are to have a shorter wait, unless you luck out and catch it after it's reopened from a downtime during the day.