Window lift motor replacement?

[MYTA21]

With the aid of the photos of the
Piper lift motors, l have been able to sort out the problems.
From those, I could see what the whole thing looked like.
The reason the window would not open from a fully closed postion was that the cam attached to the chain went past the limit switch, so by adjusting the clearance, I appear to have solved that! A screaming noise that I thought might have been related to the spring assistor turned out to be due to the manual winder bevel gear just brushing the motor bevel gear. Resolved by new spring, so as to give it clearance. Thanks for the help.