I took off the cover on the lower part of the blade arm and removed the nut. I’ve pulled firmly, but neither blade arm will budge. They’re not currently broken, so I don’t want to break them. I had a strong burning smell coming from my AC vents. Took to mechanic about a month ago, said my blower motor has a bunch of debris and even some acorns, he blew it out, no smell for about a week, give or take. I figured the smell had to work it’s way out and changed my cabin air filter. Well, the smell is still there so I was going to remove the cowl under my windshield and clean that out as well.