You don't have to remove the fender! The core comes out from inside the car. Remove the nuts (6 I think) attached to studs comming through the firewall. You do not need to remove the bolts. They attach the heater box on the engine side of the fire wall. With the nuts removed, you can pull the heater box inside the car away from the firewall. Remove the attached cable controls then you can remove the heaterbox and heater core assembly out of the car. You'll then need to remove the two brackets that hold the core inside the heater box. You may want to remove your inner glove box to gain access. Mine was already out when I did mine... Take your time, its not that tough.