How would I wire one up to a ct3.  My guess, based on looking at a 74 dt250 wiring diagram, is that the switch would be grounded to the handlebar and taps into the wire leading into the ignition coil.


Could anyone recommend a kill switch to mount on the handlebar?  I'd prefer a rocker style but as long as it works I don't care too much.

Guessing a bit but if the switch has a black plus a black/white the switch will join them together when in the off possition. Black will go to the loom earth right back to the frame at the coil mount. Sorry didn't read properly & you want to fit a kill switch. So if you find a two wire one for the handlebars, then join both wires into colors i mentioned in the headlight it should work. I once used something of a honda farm bike which had a switch you could flick right or left i think--& stayed there--like didn't have to hold it till motor fully stops revolving.
Or this type of switch push off then push on. Just don't forget to turn it on--kick kick--Bit expensive but get the idea. Ebay 401917583882