I have removed the main bearing nut from my hotpoint aquarius WM71n. Get an assistant to hold a long bar in one of the 'pockets' on the outer drum to stop the pully turning against one of the spokes. Using a good fitting socket and a length of pipe, unscrew the nut. Its locktited (thread locking glue), and very tight, right hand thread.
Chris Fairbrother, May 2006