I did that mod a few years ago on my old Atlas lathe. It works reasonably well. I reduced the backlash from 15 thou to 4 thou over most of the travel.

There are a number of different versions of the X2. Some come fitted with cast iron iron leadscrew nuts using the same principle. I found replacing them with adjustable Delrin nuts gave a significant improvement and was a low cost exercise compared to fitting ballscrews.

Russell.