It is approximately 20 min in length and takes approximately 20 min to get to the end of Main Street. If it starts at Small World at 8:50, the last float should be finishing at the gate next to the Mad Hatter around 9:30 pm. Fireworks start at 9:35 pm.
I think (but am not sure) at that time of night, they direct guests to exit on the right side (towards GCH). I know the right exit is open at that time of night. I just don't know if the left is as well.
In the picture below, purple is the parade route. Find a place in the teal or yellow area. If you sit in the teal areas, it will be slightly easier to exit than the yellow area.
Edit to add: We were shopping on Main Street between 6:30 and 7 pm a couple of weeks ago (on a Saturday). When we left, the front row on Main Street was full and the front row in the teal & yellow areas was just starting to fill. There was still plenty of room in the second or third row behind those on the curb.
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