You have to take out the glovebox, the plastic trimming above it, the A/C duct that is fixed with screws in the wall behind the glovebox, and finally, between the black plastic cap covering the evaporator and the inner side of the firewall is a white plastic cover fixed by a small torx screw and a turning knob. Remove this white cover and you will find the Microfilter. Just let know if this helped you find it, as I can post more detailed instructions if you need them.