An outer casing string, including a surface casing head, and associated installation method. In some embodiments, the surface casing head includes an outer tubular member insertable through a diverter of an installed conductor system, an inner tubular member at least partially disposed within and moveable relative to the outer tubular member, and a sleeve ring rotatably coupled to the inner tubular. The outer tubular member has an annular recess. The sleeve ring includes a snap ring that is displaceable between an extended position and a retracted position. In the extended position, at least a portion of the snap ring is received within the annular recess, and the outer tubular member is axially immovable relative to the inner tubular member. In the retracted position, no portion of the snap ring is received within the annular recess, and the outer tubular member is axially moveable relative to the inner tubular member.