I have a 1990 300E (W124) with the standard Becker radio / cassette that came with the car. One of the lamps in the faceplate that illuminates a station selection button is burnt out. Does anyone know of a suitable replacement bulb (specs - what vltage and current - and/or where to purchase) for this? I know I need to disassemble the faceplate and unsolder /resolder the bulb. Thanks.