Be carefull trying to fit an early rh switch to a later bike as the starters buttons work differently, early grounds the solenoid, later powers the solenoid
I ran into this problem just last week with my '76 GL1000. I had bought a right hand switch that had the off/ low/ high beam for the headlight and the switch had the start button single wire to ground set up. What I did was purchase another aftermarket switch for the '76 year, take it apart and then combine the top half of the switch I wanted with the '76 bottom half with the 3 wire start button.
The above fusion of the two switch halves isn't for the faint of heart! Very careful documentation of wiring before original switch removal is important!!! Also, you need to remove the vinyl sheath from the wires. In my case I had to unsolder and replace the switch wires that came with the new switches as my handlebars are a higher rise which necessitates using longer wires. The '76 GL1000 and CB750 (and earlier years) have the wires going inside the handlebars. The above wiring set up has a lot of wires to put through the bars! I ended up using short pieces of vinyl sheathing as protection for the harness where the wires enter and exit the handle bars. I also bought waxed cable lacing twine and cable stitched the entire length of the switch harness making sure all the wires were parellel to one another so the entire length of the combined wires were the smallest diameter possible. This made feeding the thicker switch harness through the bars fairly easy compared to a sheathed stock switch harness where the wires not parallel.
I have done this modification to both my CB750K and my GL1000 and everything works properly. It is time consuming and can be frustrating but it is doable.
-P.
