Using an angled rasp in the drill press, I applied a bevel to the linings. After some hand sanding, they had a nice smooth profile.
Soaking the linings in warm water for about half an hour made them soft and pliable. I cut retaining notches in the corner and end blocks, then trimmed the linings to length and cut the ends at an angle to fit the notches. I clipped them in place with a few clothespins, then let them dry in place.
Once they were fairly dry, I applied hide glue to the ribs and linings, and fit them in place. The clothespins snugged the linings up to the ribs. Next I will sand the entire surface flat, in preparation for gluing on the back plate.
I couldn't find my old labels (obviously they are in a safe place) so I took the opportunity of doing an updated design. I used the same composite image as in this website's header, showing my five completed instruments to date.