Boat is a '87 Baja Sport 220. The kill switch is not wired. Control box has yellow & yellow w/red stripe coming out the back that make the neutral start circuit. The kill switch has a purple and purple w/white stripe hanging off of it. Do I use these purple wires to interrupt the ignition "run" wire from the key switch? If not, how should they be wired?
TIA

The purple wire right off the ignition switch (run/ignition position) for the ignition kill switch. Ie:lanyard kill switch.

Or are you referencing the neutral safety switch from shifter that uses the yellow/red from ignition switch start position.

The purple ingition/run off the ignition key. That would be the one I'll need to interrupt with the two off the lanyard kill switch (in photo). Correct?

Yes.

Easy enough. Thank you.

Yup, just breaking the power from purple wire (which is ignition) when you leave the drivers seat unexpectedly. or keeping power there when driving