Abstract: A boat tower conversion kit for converting from a half tower to a full tower without the need for complete removal and/or destruction of the original half tower. A custom hard top incorporates a central core platform with several integral reinforcing plates. The plates provide structural support for the later expansion of the half tower by adding the upper tower section and upper platform(s). Leg members and ladder members of the upper and lower tower sections automatically mate with one-another in coaxial alignment, and are structurally secured to one-another through the interfacing integral reinforcing plates. Integral channels, wiring conduits and tubes provide for electrical wiring, electrical and mechanical components in conjunction with the custom platform core.