I have the same switch. It's made by Cole-Hersee, switch model M608, normally "off". Two position, "on" with button momentarily depressed. Spring return to "off". Plasticized body sealed against moisture and dirt.
Comes with M -407-03 black moisture repellent rubber button cover that snaps over special face nut. Two 18-gauge wire leads. 12" long. Mounting stem is 5.8" 32 diameer. 15/16:" long. Fits panels up through 1/2" thick. retails around $15.
I wired mine, but have the OEM outboard manual, which I left on the boat, but I believe it is simply wired between the two "M" (for magento) leads on the back of the keyswitch. I can check my manual for you ...
Thanks for the info. I think I'll go out and get one of these switches. If you would let me know how to wire it up I would appreciate it. I once wired up an hour meter to the ignition the wrong way and every time the hour meter "clicked" the motor had a hiccup. It took wuite a while to figure out that I had wired it up to the kill switch lead. I felt like a big fool!