Well is was worth the try , I have the R600 not the sport with that -+ shift option , I took it apart any way hoping I would see the same block with the little wire to change it but its totally different inside. but thanks any way the good part is the crystal is interchangeable with another receiver I tried it in . maybe some day a guy in the club will give me a positive shift transmitter and Ill be all set , thanks any way I learned something about the R600 Sport .