An overflow cover interconnection system utilizes an overflow elbow with an upper portion for insertion through an overflow drain hole in a bathtub wall; a nut, ring, or other component that fits on or around the upper portion to secure the overflow elbow in position; and an overflow cap that shields the upper portion and nut, ring, or other component from view of a user of the bathtub. The system is configured for use with bathtubs having varying wall thicknesses, without necessitating any modifications thereof.