Those Napa kits have a lot of unnecessary tools in them specific to disc brakes. Handy to have, though, if you are rebuilding rear disc brakes with internal parking brakes in them. A lot of the early GM stuff had to have the piston screwed back in before you could put new pads on. IF they were working correctly in the first place.
When you use the Lisle or Snap On scissor tool correctly, you will never bust another knuckle again. Almost takes the fun out of it. I almost never used the small end. The cup on one arm of the tool is for removing springs, the other "spoon" arm for installing springs. They give you plenty of leverage. You probably would rarely have to pull and stretch any spring to get it over a pin or hook with that small scissor end. They make a bigger version for heavy trucks. But most of the time, a heavy truck can be done with a single pry bar. Especially S-cam foundation brakes. The handled tool is for the hold down cups and springs. But a lot of the time, you can push down on the cup and twist the pin from the back of the backing plate.
This guy made me laugh, but here's how you use the tool:
