1998 BMW 323 air cabin filter

It is behind and to the left of the glove box for left hand drive cars. Remove the glove box and there is an access door with a lever/handle on it in the "box" that houses the heater core and A/C heat exchanger. The cabin filter is inside of and behind the door.

thanks for the info. i looked behind the glove box and didnt find the filter. one thing i thought of, this is a convertable! is it possible it doesnt have one.

It's there, you need to imagine it being in the center of the heater box above the transmission hump less than 12" behind the firewall.