yeah just had a look in the parts book, the bit with the arms on they call a clutch, I assume it has some flats inside the hole through the middle which locate on flats on the gear, and the two parts are held together by a circlip ?
with this in mind surely you can see what the problem is here!
dont forget the arms of the clutch must go between the raised out sections of the wheel hub so that it can be driven by the wheel's rotation...so offer the brake plate up to the hub correctly