I've replaced my blower motor and blower motor resistor in my k1500 and it still does not work... I've posted here before a few years back and txgreasemonkey was very helpful.

. Test all under hood and under dash fuses with a test light or multi-meter.
. Check if you have a relay in the circuit. If so, test it.
. Jump the motor and see if it runs.
. Review all wiring and clean grounds.
. Check the switch's continuity.

Check the connector that plugs into the blower resistor. They have a tendency to melt and not provide a positive connection.