Seeing no other way out, I disconnected the front panel. Ha, that's easier said than done as the tuning cord is deployed on both the front panel and the main chassis. Anyway, I allowed the tuning cord to hang loose in the belief that I could sort it out afterwards. That 'kinda' gave me access to the long PCB fixed to the lower part of the front panel that housed the input selection lamps. A screw at one end of the PCB was very difficult to access, then the board pushed to the side to free itself from some plastic locating pins. The faulty lamps' soldered connection leads were then, just about (!) accessible if the set was turned upside down. And so on. All in all a very difficult and testing procedure not helped by the fact that I missed one faulty bulb and had to go back to it after nearly but quite replacing the whole front panel etc. Anyway, there you go, the front panel has to be removed to change input selection lamps. Not an easy to do by any means, but 'do-able'.
