i believe you would be cutting the shaft and adapting it to the new column with a coupler similar to this
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or some other adapter/coupler to connect the column to your stock modified/cut shaft... i believe ididit makes a different style coupler also... you may have to contact them to check options... I have a MII style from setup, so i dont have first hand experience with a column and the factory box... but i did look into a while ago, prior to deciding to just upgrade the entire setup...