Hello DeeDee!
I love attending
Mickey's Not-So-Scary Halloween Party in the Magic Kingdom Park! The fireworks, the parade, the trick or treating, and the character meet and greets make this a fantastic party! It is awesome that you have already purchased your Mickey's Not-So-Scary Halloween Party! Typically, Mickey's Not-So-Scary Halloween Party officially begins at 7:00 pm and ends at midnight. Since Mickey's Not-So-Scary Halloween Party ends so late, the Monorail to
Epcot would not be running because Epcot does not usually stay open that late so you may have to adjust your plan.
I recommend parking your vehicle at the Ticket and Transportation Center (the Magic Kingdom Parking Lot) first thing in the morning before your day begins at Epcot. Then at the Ticket and Transportation Center, get on the Epcot Monorail to go to Epcot to start your Disney Day. This part of your journey can take up to 45 minutes once you park your vehicle at the Ticket and Transportation Center, according to my experience. Once you are done with your day at Epcot, take the Monorail back to the Ticket and Transportation Center and transfer to the Express Monorail to the Magic Kingdom Park. After you are done with Mickey's Not-So-Scary Halloween Party, take the Express Monorail or the Ferry Boat to the Ticket and Transportation Center to get back to your vehicle.
I hope you have a Not-So-Scary Adventure at Mickey's Not-So-Scary Halloween Party this Fall!
Marc L.