Looking for a part

I think his idea is good.
If you power up the signal side of the relay from the ig sw, and send the return through the OP sw to ground, assuming its a NO sw it should work.(I have seen some 3-wire OP switches) He could mount the relay on the firewall near the choke wiring and just splice into it there. The additional Ig.Sw.load would just be the relay coil itself. Sounds ok to me.

Ok wait. Thats what you said. Ima going back to sleep now.