Went fine after unlinking everything.
But should I collapse a reset xform modifier? Because if I select Editable poly, the body flips sideways and into a strange position, because of the Xform not being selected. And I have to select editable poly to detach parts etc. I suspect this potential problem sustains even after weighting the model, which I haven't redone yet. After resetting the xform, the xform box surrounding the model (not the white bounding box) is a bit strange. Positioned weirdly.
After unlinking and doing an xform reset:
How it looks in the Modify panel:
What happens if you disable Xform:
