I found this on Google....Originally Posted by mgrafstein
tep 1 remove glove box, 6 screws on the hing, compress glove box slightly so inner track wheels are out of slots and remove.
Step 2 go to google images and type blower motor for a 2003 or what ever year your Grand Prix is and you will find a good diagram of what you are looking for, as well you will see a picture of what the blower resister looks like.
Step 3 Now that you know what you are looking at remove the three small screws using a 6mm socket. Now the blower can be lowered and unplugged
Step 4 Look at the google image of the resister and locate directly behind the blower against the fire wall, unplug wiring leading into it. Time to remove the mounting screws, there are three screws but only two are visible. remove the two you can see and ease the resistor out the third screw hole is slotted so it does not need to be removed.
Step 5 install new resistor and plug all the wiring back in, reinstall blower and glove box. GOOD TO BLOW
Please note: The resistor screws are are a little tough to get to but if you use a 5.5 mm open ended wrench it is easiest.
Read more: How do you replace a 2002 Grand Prix blower motor resistor
