Thanks, Doc. And yes, all internal. It uses a twist shifter mounted on the end of the right side handlebar. The owner of the bike shop who built the bike, and I, had a heck of time figuring how to mount a twist shifter on a drop bar, but we did it.
It is the only bike I own that I paid someone to build, which felt strange. Coming up with, and machining the adapter for the shifter was my only contribution to the build. Well that, and a mountain of cash.