Here is a sequence of photos showing how I deal with the springs when mounting the brush plate.
Cut a piece of card stock as shown long enough to wrap around the plate. Make a hole in the middle to fit the armature shaft. (I had to add a piece to the one shown.
Put the brushes in the holder using the cardstock to hold them against the springs. Tape the cardstock around the brush holder, aligning the hole with the hole in the plate.
Place the brush holder in position While holding the assembly remove the cardstock - use scissors to cut through one side and tear it from the other.
Replace the screws and you're ready to go.