eileen could be fully conscious at the surgery...they would tell her what to expect and she would start to panic.
the torturers would place her on the operating table with her legs spread, and her head fixed in a position where she constantly watches her redhead sex. without the possibility to close her eyes. (they would remove her eyelids), they would tie her tongue to her clitoris.
and they would give her a stimulant to keep her from passing out.
they would start with her tattooed labia, they would slowly cut off her left, and then her right, and then continue with her inner labia, they would care about the clitoris, they could make sure that a small hole was drilled into the clitoris, where Eileen's sex would later hang, and then they would gradually cut off the entire cunt.
then they could cover everything with resin (or epoxy, and show everything to Eileen with the words that she is no longer a woman) and send it to mom.
but the gem would be if mom had a gift after delivery that could contain Eileen's gender in epoxy, a recording of the torture, and a phone with her daughter's number! mom would call that number in a panic and a half-dead eileen would answer and beg for help, mom would then pass out.