[PieNsky]

The blower motor is cast in and will have to be cut out. Don't freak, it was made to be cut out and has a groove to follow. Remember you have a knife in there around wires. This is easier to do with the passenger door open.
1. Open the glove box door. Release the door tensioner on the lower right corner of the door by pulling down on the cord, sliding it down and out. Push in on the sides of the door to free the door to drop down. It has an open hinge so that you may lift it out.
2. There are two screws in each corner that will be exposed when you remove the door. One holds the duct, the other will allow you to manipulate the opening. Remove the four screws and the duct.
3. Remove the screws that hold the center cover of the blower and unplug the motor.
4. There is a circular groove that you will follow with your cut. The plastic is thin so you will not need to push the knife in much. The second photo has a silver box cutter with the razor blade inserted into the groove to cut . The box cutter also prevents too deep a cut.
5. If needed, clean up your flashing from the cut, otherwise slide in your new blower and align it with the screw openings already cast in and not used. I used #8 by 3/4" screws to hold it in.
The last photo is the new blower being slid in. Notice the precast screw opening to align the one on the blower.