Glasman,
Did you adjust your front brake cylinders down? Sometimes the brake shoes have literally grooved into the drum somewhat so if the shoes are still adjusted outward, there's a lip on the drum that won't slide past the shoes. If you go to the back side of the drum, there should be an access hole into the brake cylinder where you can crank the length down to loosen the brake shoes. I had to do this on my truck.

Jon