95 blazer, drivers power window

My drivers side pw is having issue going up and down. It does run up and down, but it gets held up in approximately 4 spots up and down. It will move roughly 4 inches, and then the motor starts grinding, if I then reach up and push the window down slightly, the motor will stop grinding and continue down another 5 inches or so. This routine is the same going both up and down.

I've pulled the interior door panel off and can't see anything obviously wrong with the motor or regulator, and lubricating the rollers and track didn't help any. I guess I've got two main questions:

1. I'm leaning toward the window motor being the culprit, anybody have any experience with this?
2. And if I replace the window motor, whats the best way to mount the replacement, rivet the new one or try to bolt it on?

I just replaced the drivers window motor on my 94 jimmy. My window also hung up frequently in different spots and finally just stopped going up or down.
I used bolts but you need to be cautious that the bolts are tight in the opening and they line up very well and are not to long.

Use nyloc nuts so nothing comes loose.

The rivets work great if they come with your new motor. Use the rivets to mount the motor to the regulator. I used countersunk screws and nyloc nuts on my motor installation. It required enlarging the holes in the motor frame as the holes in one half of the motor shell are smaller to match the factory rivets and one side is larger which matched the crews I had on hand.

A careful inspection will show what I am describing. Easiest way is to use the mounting hardware supplied with the new motor.