A method of hot tapping into a multiple string configuration for obtaining access to the production tubing without removing outer layers of casing by providing a multiple casing string that includes at least an outer casing and an inner casing or production string; mounting a clamp assembly around the wall of the outer casing; hot tapping a small opening through the outer casing wall to capture any pressurized fluid through the opening; cutting first and second large openings through the wall of the outer casing to access the inner casing, each opening being approximately 180 degrees from the other opening; through the first opening, drilling a small hole through the wall of the inner casing to capture any pressurized fluid through the opening in the inner casing; and inserting an anvil through the second opening to contact and stabilize the wall of the inner casing to prevent the casing from moving while the casing is drilled.