Same here, left fork, square hole. Mine didn't come with it, so I bought one. Thankfully I wired it in and tried it before I fought inserting it into the square holder, because it is horrible (my opinion) and came right out. I have installed LED's in the turn indicator light, and they are really bright. I'm sticking with a bright indicator light instead of the buzzer. On the 550 it's got two wires: black & blue/brown. They tie into the mess of wires inside the headlight bucket.