pollen filter where is it?

Today I decided to set to and replace my pollen filter. I have a 98 facelift, 1.0 twister, which has aircon. I removed the glove box, and cut down one side of the perforated lines and bent them bck so I cud see behind. I then removed the bottom half of the black box behind the bit I had cut and all that was in that box was the heater matrix. Am I missing something?
Any help would be helpfully