I'm assuming you want to get into the housing to lubricate the bearing, as the resistor pack is mounted seperately so you don't need to touch the housing for that.

I'm assuming you know how to remove the glove box? Next, remove the bit of carpet underneath (should be 2 plastic screws attatching it just below the glove box hinge and a third screw underneath attaching it to the bottom of the fan housing).

Next, theres a bit of plastic in front of the housing, which is the feed from the blowers attached by a single screw, remove the screw and it just comes off the blower feed (may need to rotate it slightly).

Remove the power plug from the bottom of the fan casing if you haven't already done so. There are 3 screws underneath the bottom of the housing, which mounts it to the top, remove those and the fan unit and housing bottom will just drop down.

To seperate the fan unit from the bottom housing, there are three lugs on the side you have to push in with a small flat bladed screwdriver, you can then pull the fan out.

Hope that helps.