That's all you do. It's always hard for me not to make mistakes on stuff like this. You know, just like flattening the belly to much on a roller coaster and ending up with one side of the limb too thin....
Another thing easier to handle than calipers is two steel brackets, say 3" long. Take one, put bolts through the holes at each end, and add a stack of washers for spacers to each bolt. Put the other bracket on and thread on some nuts. Now you have a little rectangular spanner you can slide over the limb to look for thick and thin spots, and which you can tilt to follow the surface of the back. As you progress you can take out washers to vary the width of the span. Not so good with knotty staves.