I never really like drawing whats in-front of me, it's not a factual description or representation of how I interpretate that signifier or object. Instead I draw my reaction to that object, remember..'this is not a pipe'/..
I have had these eyes professionally made for my animatronic, i have inserted milliput into the back so i can embed the loops and ball and socket joint for the movement mechanism.
Jaw movement documentation, running off two servos using a kam system, next stage is to rig the lips that are going to run independently from the jaw movement.