Abstract: An enclosure installation assembly comprises a support base and a mounting pad adapted to be secured to the support base. The support base, having a lower portion slightly larger than its upper portion, is placed in a hole in the ground. Dirt is compacted around the support base to secure the support base in place. The mounting pad is then secured to the support base using a coupling structure that engages the support base and mounting pad so as to allow the mounting pad to move relative to the support base. Alternatively, a first portion of the mounting pad is fixedly attached to the support base. A second portion of the mounting pad engages the first portion so as to allow the second portion to move relative to the support base. Finally, an enclosure is installed on the mounting pad, with fasteners located inside the enclosure. The resulting enclosure is securely and easily installed, accessible for maintenance, and is tamper resistant.