I was wondering if it would be possible to force an NPC to switch to their backuphead when they turn to the dark side. (I want to make handmaiden turn into Asajj Ventress)

If not, could someone help me out with the script that turns Handmaiden into a jedi, so that she changes models then.

2 problems. The first is that the backup head is a game engine reference for it to switch the head to avoid duplicate appearances from occuring. Technically the Partymember NPC's should never run into this problem. The second is that there is no "OnAlignmentChange" hook for the UTC's so the best option is probably going to be changing the K_ai_master file which can have it's flaws.