Problem removing blade support from spindle

[Dave Olley]

I have a stiga ride on and on one side the two nipples that locate and support the blade have broken off, The piece on the bottom of the spindle that locates the blade should come off to allow replacement, but I can't shift it. I would like to remove the whole spindle, but have to remove this piece first to do it.
Any suggestions for freeing it would be welcome, as I have been hitting it with a hammer for an hour or two now and I'm getting weary.
Thanks

 

[bertsmobile1]

IT is aluminum so getting it off a steel shaft will be a problem
Lots of heat and a bearing type puller

 

[Forest#2]

I'm not sure on yours without a picture, BUT
On most lawn TRACTOR deck spindles if anything on the BLADE SIDE of a spindle shaft is bad, even a blade that cannot be removed I can remove the top belt pulley and take the shaft DOWN out of the spindle housing with the blade still attached to the shaft leaving the spindle housing itself in place.
After I get it removed I can then just take the shaft itself to the big vise and anvil area and use heat/big hammer or whatever it needs.

Is this an option in your case?