Thats right. After removal of the panal under the dash, you will find a rectangle cover with clips on it, just slide the clips and it should take the cover off the box and pull out the pollen filter.
Changed one today on a 2004 plate , 45,000 miler that I just bought. Absolutely black and filled with the remains of dry leaf and other debris. Hope to see a difference in the flow of air in the car now.