Onward and… well… upward.
I connected the two rows of three LEDs for the Pink Bismuth Bottle (PBB), epoxied them to the tube, and connected up the wires coming from the BBB and going to the Vaseline Bottle (VB).
The wire ends were taped down so I could keep them straight while applying a voltage to each pair and verifying the corresponding LED lit up. I don’t particularly want to find out about a bad connection after the bottle it’s inside is glued in place.
They lit up, so I glued the PBB in place. After gluing the BBB lid down, which I probably should have done before mounting the PBB LEDs, but it’s all good.