Hopefully, with the large number of clips and little number of screws that need to be reinstalled, reassembly should be simple. But some notes:

Within the orange circle is the magnet that pivots from the spring inside the trigger, which will approach the hall effect sensor on the corner of the daughterboard.

The bumpers can swing up on a pivot which can make it easier to remove the motherboard. But when trying to put the controller back together, the bumpers may get stuck. Before the main pieces are combined back together, swing the bumpers up and pull down the trigger to give the bumper room to swing down into position. Release the trigger and test.

The bottom piece by the handles have a long sleeve surrounded by a spring where it holds a long post from the top piece. Start realignment of the controller at the bottom, ensuring that these posts fall into the sleeves, then slowly close the controller at the bottom along the headphone jack, then