If the adjuster screws are not stuck you should be able to adjust them. The screw should turn inside the spindle & the end should pivit on the other side of the screw. The only time you have to release a lever is with self adjusting brakes which did not come on that model. You move the spoon up on the outside forcing down on the inside of the backing plate. Its possible you have it backed up all the way & need a good push to get it started. I'm thinking the end of the screw that goes in the shoe is froze to the screw. Put the end in a vise & turn the star wheel with a pliers. Some rust breaker will help & if its really stuck you may need to heat it with a torch.
