Remove the door panel and carefully remove the vapor liner on the door as to not tear it ans you'll be reinstalling it.
If yours is the style that has 5/16-8mm bolts holding the motor/regulator to the door then remove all three of those while holding the glass up so it doesn't drop and disconnect the two wire connector to the motor. You'll slide the motor/regulator assy out of the door and swap the motor.
If yours has the big aluminum rivets holding it together then get a 3/8 drill and 3/8 bit and drill the heads off of the rivets.
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