for a bit of cheating here is a link to take apart he rain guard and get an idea of whats involved.
Upgrade Cabin Air Filter
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carbon activated ones an be found here, you get 2 per pack.
C4 Picasso Pollen Cabin filter C4 Grand Picasso Kit Automatic AC 47XG | eBay
Okay ladies,
Here's the complete guide to installing a cabin filter. From Under8ed1's original post, read the link to give you an idea of how to remove all the bits you need, and order the C4 filter he linked (the listing has ended, but it's been relisted, so just keep clicking through till you get the current one for sale). It ends up being a different brand, but it's the same thing and the same size. It was around $30 something delivered I think. You can buy it locally in Australia but it was a bit cheaper ordering the one off Ebay, and I'm cheapskate and happy to wait the 2 - 3 weeks for it to arrive.
If you want to save more, Under8ed1 linked to one without the charcoal in it, so it's just the paper filter.
Pop the hood and remove the windscreen wiper arms. Use a small flathead screwdriver to remove the plastic lugs, then a ratchet to undo the nut on each arm. With the nut off, you can't pull the wiper straight off. Around the centre of the arm there's a flexible bend - push it towards the windscreen to straighten the arm, then pull the whole arm off the bolt. It's a piece of cake once you realise you need to straighten the arm first.
Then it's time to get those nasty little scrivets out. DO NOT use a phillips head screwdriver! Use a SMALL flat head screwdriver that fits the slot in the screw. Do NOT push downwards with any force, just put the flathead into the slot and start turning slowly with no downward force. The screw comes out very easy when you do this!
I managed to get all screws out without breaking a single one of them. With the screws out, use the flathead screwdriver to wedge under the scrivet support thing to pull it out, and put them with the screws so you don't lose anything.
Now pull everything out the three plastic shrouds, put them on the lawn and hose it all down - might as well give it a clean now.
Have a look at what's left - it's a bit dirty and the metal cover will be covered in crap.
Here's mine - a VXII with 300,000km's on the clock and it's never been cleaned before:
Now, get your missus out of the kitchen and ask her to get you the vaccuum cleaner. If you're a real man, you won't know where she keeps it so you'd better ask. Vaccuum out all the crap from this area of the car, undo the clip, pull out the wire frame and the vaccuum some more.
Here's my wire frame:
Clean off the wire frame, and pull off the foam crap as it's probably completely wrecked. Vaccuum it some more, then give the vaccuum back to your missus.
Now the filter is pretty close to a perfect size, but it's a fraction too big (just like me hehe...). Firstly, two sides of the filter have a firmer edge that extends a few mm past the filter material. Trim those few mm's off. Then, on one corner, cut it to an angle, like this (badly drawn red circles show the spots you'll need to cut/trim):
NOTE - the filter flows are a certain way - you can barely see it, but the arrow is pointing downwards in the photo. So it's the TOP side of the filter you need to trim to slide it in. You'll see what I mean once you try to fit the filter in.
You'll now be able to fit it into the slot in the car, and try fitting the metal frame back on. It's not a very good fit, and it won't slot back into the frame, but you should be able to just clip it down enough to hold it in place:
And there you go!
Now put the plastic shrouds back on, then get the scrivets back in. This is actually the hardest part of the whole thing! Those bloody scrivet "legs" need to be squeezed together and pushed in the holes. I used the small flathead screwdriver to push the legs together as I pushed it into the whole... then gently screw the screws in with the small flathead screwdriver.
Be careful with the rubber against the windscreen to align it properly, particularly on the ends of the windscreen where the bonnet supports are!
Then put the wipers back on, use the ratched to get the bolts on, then the plastic lugs on top.
Now go have a beer or three.