Microfilter Change

You get to it from the driver's footwell (If your car is RHD!). It is located next to the foot rest (next to the clutch) on top of the transmission tunnel.

I think I can remember what to do.

Remove the panel cover from under the steering column (the one with the footwell light in) and i think there is a small panel covering the filter. With these removed you should see a black plastic rectangular cover. On the cover there is a little knob that will turn to unlock the housing access door. It will only twist a little to unlock. Then remove the microfilter - try not to yank it out as it does rip and you may end up with half left inside. It is fiddly, but pull and waggle and it should come out.

With it removed use a hoover with the thin adapter to hoover inside the filter housing as mine had leaves and stuff inside.

when you put the new filter in, you will need to snap the outer plastic part (see old filter). Then wiggle it in.

Note; The filter has a tab on one end and this seats into the cover of the filter housing - on the cover it has a round recess for the tab to go in. I think the tab goes at the top and pointing towards the driver's side. I wondered why mine didn't fit in, and had to pull it out again.

I found instructions and pics on t'internet, but can't remember the address, try a search.

I think the pulley you are looking is as you say for the flaps in the ventilation system - look further towards the bulkhead (engine).

The filter housing is the last thing before the bulk head. You need to get your head stuffed right in the footwell right next to the pedals. It is more or less in line with the pedals as they get in the way when you changing the filter. As I said look for a rectangular box (about 18-20mm high and 50-60mm wide) sitting vertically but leaning at the top towards the rear of the car. It also has a sort of small lever which unlocks the cover.