Barbie Disassembly Help

Well I broke the tip of my xacto knife trying to gut the seem so gav eup on that for now. added movement point on hands shortened forearms and legs, elbows have more range, and working on making the feet/ankles more like the MU x-23 as an example. want to add the g.I. joe type waist pivot type joint and more for the head which is too big.

I customized several Barbie dolls years ago, but I never disassembled them, other than literally cutting pieces of them off. I would imagine you'd have to crack open the torso, along the seams, to free the shoulder, waist, and hip joints, and I would think the head should pop off with heating. The Barbies I customized were older models, so their knee joints were internal ratcheting affairs inside the rubbery leg material--I don't know how you could mess with those without ruining the leg. Not too helpful, I know, but hopefully, that will give you some ideas on how to proceed.