How to Change Chevy Trailblazer Heater A/C Blower Motor Fan Speed Resistor When Not Working

Replacing a blower motor resistor on a 2005 Chevy Trailblazer.
Symptoms include heater fan only working on one or a few fan speeds, or not at all.
The procedure shown in this video should also apply or be similar in the following vehicles :
2002-2009 GMC Envoy, Envoy XL, and Envoy XUV
2002-2009 Chevrolet TrailBlazer and TrailBlazer EXT
2002-2004 Oldsmobile Bravada
2004-2007 Buick Rainier
2003-2008 Isuzu Ascender