Changing the radius of the arms (shortening) will result in a longer travel of the knob to complete the shift unless you do a corresponding shortening of the levers at the side of the transmission. Rather than re-drilling holes I'd want a VERY good welder to cut a short piece out of the shift arms and weld them back together. The geometry of the column shifter is pretty critical, so "Measure twice/cut once!"
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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