1999 Chevy truck z1500 blower resistor location?

The blower motor resistor on a 1999 Chevy Silverado/GMC Sierra 1500 (Z1500) is located behind the glove box. You'll need to remove the glove box to access it. It's usually clipped or screwed into place near the blower motor housing itself. There's no single universally pictured location as the exact placement can vary slightly.