How do you remove the wiper arms on a 2002 Mercury Cougar to gain access to the wiper motor?

I just did this although I ran out of light and did not have time to diagnose my likely bad motor problem. You pull up on the back of the arm and the cover comes off revealing a 9/16" nut. Remove that then you have to literally pry the arm up and off. At first it feels like it won't come off-use the 9/16" wrench-open end and pry and wiggle it upwards. This takes a minute or two so don't give up if it resists!

on mine it was rusted solid. needed to remove to gain access to aircon filter. had to work around them, so if it's the filter you're looking after, that's the solution.