I stand corrected.

I think the part about disconnecting the wire at the bottom of the steering column is so that the horn won't blow while you are pushing down on the button. I believe if you had a quick-disconnect switch on a battery post, you could skip the part about disconnecting the wire, and just disconnect the battery instead.

Regards,
Pat O'Connor

From the 1936-42 factory service manual:

QuoteRemoval of horn button (with blowing ring)
1939-42 -- Disconnect wire at connector at bottom of steering gear. Remove screws from underside of steering wheel hub and lift off blowing ring and retainer (fig. 3). Remove screws which hold contact plate to wheel hub. Pull wire out of steering tube. To remove wire terminal, push it out of contact plate.
Removal of horn button (without blowing ring)
1939-42 -- Disconnect wire at connector at bottom of steering gear. Remove screws from underside of steering wheel hub and lift off horn button retainer and button (fig. 5). Pull wire out of steering tube.

1936-38 -- Disconnect wire at connector at bottom of steering gear. Press firmly on horn button and rotate it to the right as far as it will go. Relieve pressure and button will pop out.

Phred-

Not sure about the '37. If I recall correctly, on my '36, you push down on the horn button, and twist it counter-clockwise.

Regards,
Pat O'Connor
Magnolia, IL

How does the horn button remove from the steering wheel on my 37 P4?

Thanks in advance!