Buy more miscellaneous parts

I bought some milky-clear polyethylene tubing with a 1/2" outside diameter and a 3/8" inside diameter. It's easily large enough for lights and wires, and I decided on terminating it with 3/8" steel pipe which has an inside diameter that snugly holds the polyethylene tubing. I went with fender washers, 3/8" bolts, and pipe clamps to make the pupils of the eyes.

To connect the light tubes to the electronics, I went with DB-25 connectors with hoods. I should be able to crimp the tubing into the hoods and make a reasonably weather-tight fit.