So yes, hello. I just did this on my '76 750F. Do you have an F bike or a K bike?
The LH switch for the 75/76 F is different from the 77/78 F (and K) switch in that the latter has four of the wires converging in a 4-prong plug, and three of the wires have female connectors. All of the wires are the same, except for the black/yellow wire on the 75/76 is a brown/red on the 77/78. Both of the LH switches have neutral safety switches on them as well - which are 2 wires that come out of the clutch perch. Spanner1 came over last night and cut off the plug and two of the female connectors and installed male bullet connectors (available from vintageconnectors.com). Now it will hook right up. Good luck!