Step 4: Find and Remove Roofing Nails for Bad Shingles.
That's where the long pry bar come in.
To remove this shingle (under pry bar), you will have to remove nails located under the next two higher shingles. It wasn't long before I just ripped off much of the shingle I was removing.
The second photo here shows the head of a roofing nail protruding about 1/4" after I had hammered it out from below. Otherwise I would have had to dig into the shingle to get under the nail head.