FP+ parade viewing (for both Festival of Fantasy and MSEP) is on the inside northern edge of the hub. Right on the street so that the parade will pass between you and the castle.
I've never done it before, but I've researched the heck out of it. My understanding is that it's a rather large arc (about 150 degrees) across the north inside edge of the hub and that they strictly limit the number of FP+s granted for that area. As such, there's not only a lot of elbow room, but you might even be able to sit on the ground and move about in the FP+ viewing area.
Again...not my experience...just my understanding. If anyone else here has any insight into it, I'm sure we'd all love to hear it.