Dedicated steering wheel pullers for vintage vehicles with the horn wire up the center of the shaft have a flat foot on the jackscrew with a slot for the horn wire to stick through. I started using one like that in the late 1950's. Pull the wire up a little and bend it sideways, then position the foot so the wire isn't damaged. A regular flat puller foot and a cutoff wheel on an angle grinder will get you in business in less than a minute.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!