SPi and Nikolai Belinski a.k.a. Bogdan managed to come up with a method of making IW6 AI models compatible to iw3-4-5 skeleton.
We can share our edited skeleton here for you all to use.
There are 3 versions of the skeleton.

• For fullbodymodels
• For headmodels
• For bodymodels

The method is the following.
 

• Dragdrop our edited skeleton in the Maya scene.
• Dragdrop the IW6 AI model in the Maya scene.
• Remove IW6 Skeleton.
• Dragdrop the IW6 bind file.
• Remove the following bones from our edited skeleton:

j_coatfront_le
j_coatfront_ri
j_coatrear_le
j_coatrear_ri
j_pelvishelper_le
j_pelvishelper_ri
j_latiss_le
j_latiss_ri
j_teres_le
j_teres_ri
j_pectoral_le
j_pectoral_ri
 

• Under j_head keep ONLY the following bones and remove all other:

j_head_end
j_helmet
j_jaw
tag_eye
 

• Rename the following bones:

j_kneehelper_le -> j_knee_bulge_le
j_kneehelper_ri -> j_knee_bulge_ri
j_wristfronttwist1_le -> j_wristfronttwist_le
j_wristfronttwist1_ri -> j_wristfronttwist_ri
 

• Your model should be ready for export.

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