I used a flushmount 5 pole watertight marine connector. It comes with a watertight cap when you want to run w/o the tower on. There are two kinds. The one I have is right angle for side mount, which is the one shown, the other is straight for top mounting. The base Bolts onto the boat with stainless hardware and a rubber washer. The conector (top half) disconnects instantly by unlocking the clip and pulling the connector up and off. Really quite strong. Available from West Marine.
(Message edited by charlie on July 31, 2003)