Case-grounded, on a switched ground circuit? The original application applied switched power to a constantly grounded horn, right? Just making sure my brain is working-it is after working hours.

To make them work, electrically isolate the mounting from the rest of the chassis. Apply constant (but fused-more on this later) power to the power hookup, then connect a wire to the case and through the switched ground circuit.

Caveat: applying 12 volts to something intended for 6 can cause shortened component life, overheating, arcing, fire, and general bad stuff to happen, hence the importance of fused power. I personally wouldn't do this install. If you do it, it's probably better to use a key-switched hot instead of always-hot. That way, you won't be able to use the horn with the key off, but the horns won't self-destruct without you around.

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83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
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