Hi Megan!
So you'd like to experience both
Fantasmic! and
Star Wars: A Galactic Spectacular, Hollywood Studios' amazing Star Wars-themed nighttime fireworks show? I feel your pain. I love them both, and on my upcoming visit to Walt Disney World Resort I have the same dilemma. With the 7:30 showing of Fantasmic! having a duration of 30 minutes, and the fireworks beginning at 8pm, it's hard to do both - but I'll tell you my plan.
If you have your heart set on catching the fireworks, you'll need to make an early exit from the Hollywood Hills Amphitheater at the end of Fantasmic!. (The end of the show is really cute, so try and stay as long as you can!) When you enter the amphitheater, try to find a seat on the upper right of the seating area. That's where you'll need to be to make a quick exit at the end of the show. The exit pathway will take you to the front of the park - you'll end up right in front of the Crossroads of the World gift shop.
The Star Wars fireworks can be viewed from virtually any spot on Hollywood Boulevard. My advice would be to try and make it at least halfway down Hollywood Boulevard, toward the Great Movie Ride, if possible. If the crowd is too thick to maneuver through, you can still enjoy the fireworks, even from the entryway of the park. The only part of the show that may be difficult to see are the projections on the Chinese Theatre (The Great Movie Ride).
I hope this helps, and you're able to catch (most of) both shows on the night you visit
Disney's Hollywood Studios. May the Force Be With You! - Diane W.