Last year I wanted all morning fast passes. I initially booked them all for the evening then moved them individually to the morning times I wanted.
Pick your 3 and it'll give you options to select which group you like best then from there you can go into each one individually and change the times if they're available after you picked the original times
While shuffling around FP+ reservations, remember that you can only change times for one FP+ reservation at a time, and since the system won't allow overlapping FP+ windows you may not see all the available times for the attractions you want. (So Peter Pan might have a 10:55am slot open, but your 10am-11am Space Mountain FP+ is keeping you from seeing it)
If you want to get into choosing very specific times and order of attractions, your best bet is to do as @geodon34 suggests, make all of them initially for the evening. This leaves the morning wide open for you to then move them into available time blocks individually. (Make sure to move the most difficult-to-get ones first and then work around that)
-Rob
I think the trick with FP+ is going back individually once the first times are set. Disney is going to recommend times up front, and it's much easier to go back into each one individually then to try and make it perfect at the start. It's a clunky system.
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