Bob, I've had to do this a couple of times, and have found the easiest way was to remove the whole blower assembly. This assembly bolts to the firewall in three or four places, and once these machine screws are removed the whole blower fan and housing just drops out. Be carefull not to bend the cables that control the freshair vent located on the right side of the housing, or simply disconnect it from the vent actuator. You then can remove the glove box out the back side and have ample room to do the heater core. Really not difficult but takes a little time, time well spent. This explanation is kind of quick and dirty, but once you get into it, it is fairly easy to see what needs to be done. Dan