@verminsup First, are you SURE those are BLDC motors?
I see a ribbon cable coming out of the encoder, and a two-wire connector coming out of the back of the motor, so I think they are DC motors with an incremental encoder.
Let's start there and see what you need for a motor-position controller after determining what kind of motor you have.
If you can post:
What Stratasys machine you are trying to convert
Links to any documents for that printer
Close-up photographs of the motor connections
Names, numbers or other markings on the motors you are trying to control
It would help a LOT.