If I read this right, you have the blade drive mechanism removed from the cutter deck? The spindle you refer to is held in by the blade bolt at the bottom and the drive pulley bolt on the top. If you can hold the damaged spindle in a vice you should be able to remove the pulley bolt and lift the pulley off. Then, the shaft can be driven from the bearings by careful use of a hammer, accompanied by lots of WD40 to help it along. Take care though - you don't want to damage the spindle end so that it becomes burred over, and impossible to pass through the bearings. Hope this helps...!
John
May 2008