replacing wipers on 90 lesabre

I've got a 90 Lesabre with completely shot wiper blades, so I bought new ones (the entire mechanism) but I can't for the life of me get the old ones off. I've never had this problem before. Does anyone know how to remove the wipers from a 1990 Lesabre?

The 90 lesabre's wiper arm has a pin on the side of it and the blade assembly just presses on it. You just use a screwdriver and pry the wiper assemble off the pin and away from the arm.