Rear Brakes

You probably need to "un-adjust" the brakes first. As the shoes wear into the drum a ridge forms and the brake shoes get caught behind it and the drum will not come off. If the "un-adjustment" doesn't work you can force them off by using 2 metric bolts in the threaded holes in the drum. Put the bolts in to the holes and turn evenly on each one till the drum pops off. But be careful and have new brake hardware handy as you will break at least the retaining clips and springs.