Great DIY, attempting this on my own now, though not sure if I'll have replace the blower motor.
In my case, no air comes out of the vents at all, however I can hear the blower motor rolling just fine. I've tried all sorts of combinations, A/C on, A/C off, min fan speed to max fan speed, but no air was blowing whatsoever...
Then I removed the glove box and the air tube, and voila, that shutter (flap?) that would make air travel thru the air tube appeared to be plain shut all the time.
Has this something to do with the blower motor, or something else let's say the final stage resistor unit (FSU)?
Thanks for the help!