While someone applies upward pressure on the inner basket
(just grab by the lip an pull up). take the end of the spanner wrench or blunt chisel or like object
and with a metal hammer beat down on the top edge of the metal drive block (the part you screwed the nut off of)
making sure not to damage the threads or hit on the 2 internal grooves..anywhere else on the top of the block is fine.
a few good knocks should break it free...if not rotate the inner basket a little and try again. This will
only work if someone is holding up on the basket.
Source: Removing the inner basket in a Whirlpool LSV7245AQ0 washer