i have read that they make a adpt. plate to install a 1999-2004 jeep power steering box in a 1951 mercury & you can keep your origanal steering colum has any one on the hamb done this.
http://americanpowertrain.com/i-8580036-ez-electric-power-steering-for-street-rod-and-customs.html pricey, but the more i look at this, the more i like it. use the ends of your column and this hides under the dash