My water tower is modeled after the vintage type tower I grew up with in a small Iowa town. The guy wires a pieces of filament threaded the holes and glued in place. The pipe is hollow to run wires through. The top of the ladder is not glued onto the top and the top is not glued to the tank to enable wiring and a blinker circuit if desired. I drilled an 1/8" hole in the top from the inside to hold a 3mm LED and glued it with CA as I did for the entire tower.