I had the radio for my 50 converted to FM. The radio is untouched except an FM receiver that introduces the signal before the final amplifier. It is operated by turning the radio on and off within a 5 second interval. Estimate the FM dial. Very samll circut board that does not hack up the original radio and you get the sound from the tube amp and stock speaker. There lies my problem with the conversion. Even with sound insulated cab once you get moving down the highway with window open the radio has to be turned all the way up and still is boderline for volume. This in either the original AM mode or FM. I ended up putting a 6 cd changer under the seat and a remote controlled head unit in the glove box.
