The Buell switch has 4 terminals. Remove it and unplug it from the harness.
The Kawasaki switch has 6 terminals because the leads for the brake light switch are included and ran cleanly in the single wiring sleeve instead of separately like Buell does. They pop out of the Kawi housing on a short pigtail and have the correct connectors for the Buell switch.
You can either leave the brake light wiring completely alone, and ignore the 2 black wires in the Kawi plug...
or go ahead and unplug the 2 stock wires from the stop light switch right under the brake lever pivot, and pull them through into the wiring area behind the windscreen
Now you have the open 4 terminal plug and 2 open .110 female spades for the brake light switch. 6 total, just like the Kawi plug. See? I told you this was easy.
Now chop off the green Kawi plug.
You will have:
(2) Black wires, these are for the brake light switch, direction doesn't matter, thats why they are both black, put on the .110 male spades and plug them into the stock Buell female spades you just pulled off the switch.
(2) Black wires with a red stripe. These are for the starter button. Again, the direction doesn't matter so put them in the #1 and #2 spot in the new Buell plug, or butt connector to the red striped Buell wires (Black/Red and White/Red) in the old plug.
(1) red and (1) Yellow/Red stripe left for the Run switch! and you guessed it. Direction doesn't matter here either. Plug them in the remaining holes (#3 and #4) or butt connector to the Grey and White/Black on the Buell plug you chopped off your old switch.
Buell AMP terminals crimped on the Kawi leads:
See the terminal numbers on the plug, thats where the Kawi wires go:
* The female connector on the Buell wire harness side has different colors going into it (A freaking pet PEEVE of mine) so don't look at it, it will only confuse.
Now test your handiwork!
Make sure the run switch is off and turn the ignition on. Check the brake light operation.
WITHOUT turning on the run switch, press the starter button. Nothing should happen. IF you hear the fuel pump prime, you have reversed the (#1 and #2) and the (#3 and #4) wire pairs. Keep those pairs together and switch them in the plug socket to the other side.
If nothing happened when you pressed the starter button, it's ok check your neutral light, turn on the run switch (fuel pump should prime), hit the starter, and wheelie the **** out of your new rad ride.