An antenna system includes a detachable assembly including a circuit board that is connected to a cover by a resilient member. A bezel is adhesively attached to the glass of a vehicle having conductive antenna elements on the vehicle glass. The bezel includes guide surfaces and locating surfaces that accurately position the circuit board and antenna feed wire relative to the vehicle glass. The cover and circuit board can be detached from the bezel for servicing of the circuit board, and the guide and locating surfaces of the bezel provide for accurate positioning of a replacement detachable upper assembly during servicing/repair of the antenna system.