I'm not sure limiting the power would decrease the scan angle, as the steppers would still take just as many steps, they would just be slower as the magnetic fields aren't as great. Since they don't need to completely rotate, if you could find which wires are the 2 end coils, you could possibly disable them, essentially cutting those coils out of the circuit, though the steppers may not have too many coils either.
EDIT: Looks like they are only using 4 coils anyway, you have 5 wires going to each stepper, one is a common ground, the rest are individual coils I believe.
EDIT: Looks like they are only using 4 coils anyway, you have 5 wires going to each stepper, one is a common ground, the rest are individual coils I believe.
