Sport440,
I am trying to understand how installing the rack offset from center will result in an uneven turning radius. If is if offcet you can compensate by adjusting the length of the tie rods. (longer on one side than the other). The lock to lock distance would remain the same on both sides. I can steer uneven bump steer problems bit not differential turning ability. unless of course the design is such that the rack is so far offset that it reaches its limit of travel in one direction before the wheel/spindle reaches its full travel.

I got lucky, in designing the rack for my 56 I was able to use a center steer rack and I can use long tie rods that attach within an inch of where the OEM rods attached to the centerlink so there is no bump steer issues.
Scott