It should be obvious. The radius arms are angled in towards the center of the vehicle, so the longer they become, the further inboard of the frame they will be. Your particular radius arm bushing has nothing to do with this, they are all the same.
I built a new cross member to support the 203 205 doubler and have spots to mount the radius arms to it. you just have to make sure that your track is right(distance from front to rear is the same) and your axle is centered.