1989 johnson 100 overheat warning light along with oem alarm horn

[tlocus73]

Hello,
Seems I recall seeing a post where someone modded an LED or light if engine overheated. Can't seem to find it.
I'd like to wire up a warning light (along with my alarm horn which sometimes is hard to hear).

Correct me if I'm wrong, when the temp sensors in the cylinders sense an overheat, they ground out (tan wire)?... Does this create a circuit for the alarm horn to sound off? If so, at 12VDC?

And info, help appreciated.

t

 

[emdsapmgr]

Each head has a temp switch. It's an on-off deal. When the switch (that brown wire) on either head senses head temps of 212 degrees, it goes to ground and turns the hot horn on. (The horn will shut off when the cyl head temps go back down to 175 degrees-still too hot for normal running.) Why put a light on the dash, when you could add a simple temp gauge instead?