Take a LEFT out of the Dolphin onto Epcot Resorts Blvd. At the traffic light, take a RIGHT onto Buena Vista Drive. Take the first RIGHT onto World Drive.
Follow the signs for the Magic Kingdom. You'll need to change two lanes to your left to avoid going to Epcot. When you get to the Magic Kingdom toll plaza, stay to the far right. Once through the toll plaza, the road forks. Stay right, and then stay right again for another immediate fork. You are now on Vista Blvd.
After some windy turns, you'll come across the entrance to Fort Wilderness. You want the SECOND entrance. There will be a closed guard shack right next to the entrance. Park in that lot.
From this point, you will need to take a Fort Wilderness Internal shuttle bus. Board any bus marked "SETTLEMENT" and take it to the Settlement Depot. Color does not matter. Buses run every 10 minutes. The Settlement Depot is where Pioneer Hall is located.
For your return, board any bus marked "OUTPOST." These buses run on the :10 minute mark, and will take you to the Outpost Depot where your car is located.
When you exit out of the parking lot, you'll want to take a LEFT onto Vista Blvd. When you come to a traffic light, take a RIGHT onto Bonnet Creek. Follow Bonnet Creek till it ends, at Buena Vista Drive. Take a RIGHT. Follow Buena Vista Blvd until you hit the Epcot Resort area. I'm sure you can handle it from here.
By the way... on a side note... I don't usually work nights, but I picked up an overtime shift a few weeks ago at night in Fort Wilderness. I noticed they're now running Resort buses from the Settlement after the Hoop. Not sure if they do this for all the shows, but they did for the last show on that particular night.