In the above pic, you can see the pads, spring and shim [tabs] (which I think is apart of the spring)
The pad is inserted between the shim tabs to minimize squealing later.
Unsticking the brake cylinder, easy, squeeze the brake lever, keep pumping until it pops out. Add fluid if necessary.
That said, use a c clamp and a brake pad to press in the cylinder 1st to break it loose if you find the 1st method too tough.
Please realize he did state don't do it if you're not going there and getting pics of the whole thing is worth doing for many that'll never see it apart.