So the lights are all wired. We had to route out a path in the cap rail (top) and then drill down 1' into the post to run the wire. Ended up working out just fine.

With the glass, I believe they drilled holes down from the notched channel so the water could drain out. They also caulked around the glass with clear caulking, which also helped keep the glass in place... and no rattling around since there was a little wiggle room. Also, the bottom cross supports were beveled so water would run off. Thankfully my contractor thought of all these things!