I can't remember the name of this brake, but it is difficult.  If you have what I am thinking about, there is a "can" about 4" in diameter and maybe 6" long, with a hy line running to it.  On the back of the "can" you will need a 3/4" wrench to release the brake.  The remove the hy lines going to the "can"  There is a large locking nut at the backing plate.  Loosen the nut, and then rotate the "can" out of the backing plate. Some hy oil will spill all over the place, so be ready for it.

Inside the brake, the shoes are actuated by two large wheel cylinders.  They are auto adjusted internally.  How ? No one knows.

Hope this helps.  To back them off with the star wheels, I am not sure if it can be done.