I've seen too many accidents on the racetrack with cut/welded steering shafts to ever try that, plus the bushings in the mast jacket won't let a sleeved shaft pass through them unless the sleeve is turned down to original diameter. The steering shaft is hollow in most cases to let the horn wire pass through it, so you're dealing with a limited thickness of metal to begin with. How about adapting a tilt wheel assembly and a more modern steering gear, with a flex joint below the column?
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
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