Following the Allied victory at Tulagi and Gavutu–Tanambogo, Munro and Evans were among Coast Guard and Navy personnel who staffed Naval Operating Base (NOB) Cactus at Lunga Point on the northern coast of Guadalcanal. NOB Cactus served as a communication hub between land forces and offshore vessels. Established on August 9 by Coast Guard Commander Dwight Dexter, NOB Cactus is the only known instance of a naval operating base primarily led by Coast Guard personnel. Munro volunteered for assignment at Lunga Point; Dexter was his favorite officer.