Toshiba BTD-200QF baxis removal

We have a BTD-200QF, S/N 144463, MFG. Date 2002-2 that we purchased used. We were unable to get repeatability out of our B axis positioning as we had .006 slop in the worm.
We were able to tighten the lock nut P/N 59 and reduce this to .003 but we believe the worm will need replaced. That being said we are not sure of the procedure for removing the shaft to inspect and determine what parts will need replaced. Is there a procedure available for this? Can anyone supply any guidance?