I restored all the trim rings on my Duster. I didn't do anything with the spot weld. I carefully loosened the pinch around the perimeter on the inside. The inner mounting portion flexed enough that I was able to gradually work it out of the outer portion in a manner like the reverse of installing a tire over the bead of a rim. After the two pieces are separated, you will have access to remove dings from the back surface. I put the 2 halves back together in reverse order and carefully closed the pinch seam.
This was my first attempt at working on Rallye wheels and I was very happy with how they turned out. Like all stainless steel work, it is a slow tedious process to get it to looking right but it can be done by the home car enthusiast.